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Sample records for accelerated rate compared

  1. 1-year retention rates and performance ratings: comparing associate degree, baccalaureate, and accelerated baccalaureate degree nurses.

    PubMed

    Weathers, Suzanne M; Raleigh, Edith D Hunt

    2013-09-01

    The purpose of this study was to examine 1-year retention and managerial performance ratings of newly licensed RNs (NLRNs) according to nursing education program types (associate degree, traditional baccalaureate, and accelerated 2nd degree baccalaureate). Findings revealed retention and performance differences, suggesting the possibility of tradeoffs related to educational program type when selecting NLRNs for open positions. PMID:23958525

  2. On Comparing Transition Rate Gains.

    ERIC Educational Resources Information Center

    Reuterberg, Sven-Eric

    This report is about the problem of making transition or enrollment rate gains comparable. It is shown that measures based on the proportions themselves, i.e. the difference between proportions, the proportion ratio and the residual gain ratio do not make the gains comparable. Instead a non-linear transformation has to be done. Two such…

  3. Accelerating the Rate of Astronomical Discovery

    NASA Astrophysics Data System (ADS)

    This meeting marks the the International Year of Astronomy by reviewing the extent to which astronomers are achieving the optimal rate of astronomical discovery. Can we identify and overcome the limits to progress? What steps can be taken to accelerate the rate of expansion of astronomical knowledge? What lessons can be learnt both from the recent and distant past? As the public announcements regarding the 2009 IYA have emphasized, new astronomical discoveries are currently being made at an extraordinary rate, while the invention of the telescope ushered in an equally momentous "golden age of discovery" 400 years ago. The meeting addresses a range of potential limits to progress-paradigmatic, technological, organizational, and political-examining each issue both from modern and historical perspectives, and drawing lessons to guide future progress. The program focusses on how astronomy actually progresses, using careful historical studies and real data, rather than anecdotes and folklore.

  4. THE SPECIFIC ACCELERATION RATE IN LOOP-STRUCTURED SOLAR FLARES-IMPLICATIONS FOR ELECTRON ACCELERATION MODELS

    SciTech Connect

    Guo, Jingnan; Emslie, A. Gordon; Piana, Michele E-mail: piana@dima.unige.it

    2013-03-20

    We analyze electron flux maps based on RHESSI hard X-ray imaging spectroscopy data for a number of extended coronal-loop flare events. For each event, we determine the variation of the characteristic loop length L with electron energy E, and we fit this observed behavior with models that incorporate an extended acceleration region and an exterior 'propagation' region, and which may include collisional modification of the accelerated electron spectrum inside the acceleration region. The models are characterized by two parameters: the plasma density n in, and the longitudinal extent L{sub 0} of, the acceleration region. Determination of the best-fit values of these parameters permits inference of the volume that encompasses the acceleration region and of the total number of particles within it. It is then straightforward to compute values for the emission filling factor and for the specific acceleration rate (electrons s{sup -1} per ambient electron above a chosen reference energy). For the 24 events studied, the range of inferred filling factors is consistent with a value of unity. The inferred mean value of the specific acceleration rate above E{sub 0} = 20 keV is {approx}10{sup -2} s{sup -1}, with a 1{sigma} spread of about a half-order-of-magnitude above and below this value. We compare these values with the predictions of several models, including acceleration by large-scale, weak (sub-Dreicer) fields, by strong (super-Dreicer) electric fields in a reconnecting current sheet, and by stochastic acceleration processes.

  5. A count rate based contamination control standard for electron accelerators

    SciTech Connect

    May, R.T.; Schwahn, S.O.

    1996-12-31

    Accelerators of sufficient energy and particle fluence can produce radioactivity as an unwanted byproduct. The radioactivity is typically imbedded in structural materials but may also be removable from surfaces. Many of these radionuclides decay by positron emission or electron capture; they often have long half lives and produce photons of low energy and yield making detection by standard devices difficult. The contamination control limit used throughout the US nuclear industry and the Department of Energy is 1,000 disintegrations per minute. This limit is based on the detection threshold of pancake type Geiger-Mueller probes for radionuclides of relatively high radiotoxicity, such as cobalt-60. Several radionuclides of concern at a high energy electron accelerator are compared in terms of radiotoxicity with radionuclides commonly found in the nuclear industry. Based on this comparison, a count-rate based contamination control limit and associated measurement strategy is proposed which provides adequate detection of contamination at accelerators without an increase in risk.

  6. ON PARTICLE ACCELERATION RATE IN GAMMA-RAY BURST AFTERGLOWS

    SciTech Connect

    Sagi, Eran; Nakar, Ehud

    2012-04-10

    It is well known that collisionless shocks are major sites of particle acceleration in the universe, but the details of the acceleration process are still not well understood. The particle acceleration rate, which can shed light on the acceleration process, is rarely measured in astrophysical environments. Here, we use observations of gamma-ray burst (GRB) afterglows, which are weakly magnetized relativistic collisionless shocks in ion-electron plasma, to constrain the rate of particle acceleration in such shocks. We find, based on X-ray and GeV afterglows, an acceleration rate that is most likely very fast, approaching the Bohm limit, when the shock Lorentz factor is in the range of {Gamma} {approx} 10-100. In that case X-ray observations may be consistent with no amplification of the magnetic field in the shock upstream region. We examine the X-ray afterglow of GRB 060729, which is observed for 642 days showing a sharp decay in the flux starting about 400 days after the burst, when the shock Lorentz factor is {approx}5. We find that inability to accelerate X-ray-emitting electrons at late time provides a natural explanation for the sharp decay, and that also in that case acceleration must be rather fast, and cannot be more than a 100 times slower than the Bohm limit. We conclude that particle acceleration is most likely fast in GRB afterglows, at least as long as the blast wave is ultrarelativistic.

  7. Accelerating degradation rate of pure iron by zinc ion implantation.

    PubMed

    Huang, Tao; Zheng, Yufeng; Han, Yong

    2016-12-01

    Pure iron has been considered as a promising candidate for biodegradable implant applications. However, a faster degradation rate of pure iron is needed to meet the clinical requirement. In this work, metal vapor vacuum arc technology was adopted to implant zinc ions into the surface of pure iron. Results showed that the implantation depth of zinc ions was about 60 nm. The degradation rate of pure iron was found to be accelerated after zinc ion implantation. The cytotoxicity tests revealed that the implanted zinc ions brought a slight increase on cytotoxicity of the tested cells. In terms of hemocompatibility, the hemolysis of zinc ion implanted pure iron was lower than 2%. However, zinc ions might induce more adhered and activated platelets on the surface of pure iron. Overall, zinc ion implantation can be a feasible way to accelerate the degradation rate of pure iron for biodegradable applications. PMID:27482462

  8. Accelerating degradation rate of pure iron by zinc ion implantation

    PubMed Central

    Huang, Tao; Zheng, Yufeng; Han, Yong

    2016-01-01

    Pure iron has been considered as a promising candidate for biodegradable implant applications. However, a faster degradation rate of pure iron is needed to meet the clinical requirement. In this work, metal vapor vacuum arc technology was adopted to implant zinc ions into the surface of pure iron. Results showed that the implantation depth of zinc ions was about 60 nm. The degradation rate of pure iron was found to be accelerated after zinc ion implantation. The cytotoxicity tests revealed that the implanted zinc ions brought a slight increase on cytotoxicity of the tested cells. In terms of hemocompatibility, the hemolysis of zinc ion implanted pure iron was lower than 2%. However, zinc ions might induce more adhered and activated platelets on the surface of pure iron. Overall, zinc ion implantation can be a feasible way to accelerate the degradation rate of pure iron for biodegradable applications. PMID:27482462

  9. Traditional and accelerated Ponseti technique: a comparative study.

    PubMed

    Elgohary, Hatem S A; Abulsaad, Mazen

    2015-07-01

    The purpose of this study was to compare the results of traditional and accelerated Ponseti techniques to clarify whether this technique can be done safely in reduced time with complete correction of the deformity and without complications. A total of 66 feet in 41 children with idiopathic club foot and with Pirani score no <4 were included; of these, 34 feet in 20 children were managed with the traditional Ponseti method with one cast a week, in the other 32 feet in 21 children, an accelerated technique was used with casting twice a week, and the Pirani score was used for initial assessment and for follow-up. The results were comparable for both groups; the mean number of casts for full correction was 4.88 ± 0.88 in the traditional group and 5.16 ± 0.72 in the accelerated group. Initial correction was obtained in all cases in both groups, and relapses were observed in 14.7 % in the traditional group and in 15.6 % in the accelerated group. Deformities required from four to seven casts for correction in both groups. There was a statistically significant reduction in the mean time required for correction from onset of manipulation till tenotomy or correction of equines without tenotomy which was 33.36 ± 6.69 days (21-42 days) in the traditional Ponseti group and 18.13 ± 3.02 days (11-22 days) in accelerated Ponseti (P = 0.001). Accelerated Ponseti technique significantly reduces the correction time without affecting the final results; it is quite as safe and effective as the traditional Ponseti. PMID:25633123

  10. Acceleration of the rate of ethanol fermentation by addition of nitrogen in high tannin grain sorghum

    SciTech Connect

    Mullins, J.T.; NeSmith, C.C.

    1987-01-01

    In this communication, the authors show that accelerated rates of ethanol production, comparable to sorghum varieties containing low levels of tannins and to corn, can occur without the removal of the tannins. The basis of the inhibition appears to be a lack of sufficient nitrogen in the mash for protein synthesis required to support an accelerated fermentative metabolism in Saccharomyces. No inhibition of the enzymes used for starch hydrolysis was found.

  11. High data-rate atom interferometer for measuring acceleration

    SciTech Connect

    McGuinness, Hayden J.; Rakholia, Akash V.; Biedermann, Grant W.

    2012-01-02

    We demonstrate a high data-rate light-pulse atom interferometer for measuring acceleration. The device is optimized to operate at rates between 50 Hz to 330 Hz with sensitivities of 0.57{mu}g/{radical}(Hz) to 36.7{mu}g/{radical}(Hz), respectively. Our method offers a dramatic increase in data rate and demonstrates a path to applications in highly dynamic environments. The performance of the device can largely be attributed to the high recapture efficiency of atoms from one interferometer measurement cycle to another.

  12. Comparative study of acceleration transducers for biomedical applications

    NASA Astrophysics Data System (ADS)

    Buchczik, Dariusz; Wyżgolik, Roman; Pietraszek, Stanisław

    2006-10-01

    The results of comparative studies of the metrological parameters of acceleration transducers constructed in Institute of Electronics, Silesian University of Technology is presented in this article. The construction of the transducers is based on commercially available monolithic accelerometers and optimized for biomedical applications. The parameters determined during the tests are similar to the parameters of the monolithic accelerometers declared by their manufacturers. It proofs that both the mechanical and the electronic construction of the transducers are correct.

  13. Unexpectedly large dose rate dependent output from a linear accelerator.

    PubMed

    Cheng, P C; Kubo, H

    1988-01-01

    During our routine calibration of a Varian Clinac-20 linear accelerator, the absorbed dose for a fixed monitor unit (mu) was found to decrease with increasing dose rate. Between dose rates of 100 and 500 mu/min, there was up to 20% difference in absorbed dose for a 20-MeV electron beam. The cause of this problem was a failure in the electronics circuit of an integrating board. This paper presents our analysis of the problem and suggests a possible means of isolating such a failure to warn technologists, physicists, and engineers. PMID:3141760

  14. SCIRAS sensor - Sundstrand Coriolis Inertial Rate and Acceleration Sensor

    NASA Astrophysics Data System (ADS)

    Hulsing, Rand H., II

    The evolution of the design of SCIRAS (Sundstrand Coriolis Inertial Rate and Acceleration Sensor) from operational theory through three generations of hardware is discussed. SCIRAS measures both angular rotation and linear acceleration and is suitable for a full three-axis inertial navigation package replacing conventional clusters of gyros and accelerometers. Using only accelerometers, the package can be made smaller, lighter, and at less cost than equivalent performance sensors. Since a microprocessor is included, thermal modeling, misaligment correction, and size effect corrections can be made providing 'ideal' delta velocity and delta angle in digital format to a navigational computer. Since the sensor is all flexure, it has no wearout, is extremely rugged, and requires no special backfill, sealing, or maintenance.

  15. Comparing current cluster, massively parallel, and accelerated systems

    SciTech Connect

    Barker, Kevin J; Davis, Kei; Hoisie, Adolfy; Kerbyson, Darren J; Pakin, Scott; Lang, Mike; Sancho Pitarch, Jose C

    2010-01-01

    Currently there is large architectural diversity in high perfonnance computing systems. They include 'commodity' cluster systems that optimize per-node performance for small jobs, massively parallel processors (MPPs) that optimize aggregate perfonnance for large jobs, and accelerated systems that optimize both per-node and aggregate performance but only for applications custom-designed to take advantage of such systems. Because of these dissimilarities, meaningful comparisons of achievable performance are not straightforward. In this work we utilize a methodology that combines both empirical analysis and performance modeling to compare clusters (represented by a 4,352-core IB cluster), MPPs (represented by a 147,456-core BG/P), and accelerated systems (represented by the 129,600-core Roadrunner) across a workload of four applications. Strengths of our approach include the ability to compare architectures - as opposed to specific implementations of an architecture - attribute each application's performance bottlenecks to characteristics unique to each system, and to explore performance scenarios in advance of their availability for measurement. Our analysis illustrates that application performance is essentially unrelated to relative peak performance but that application performance can be both predicted and explained using modeling.

  16. SpS5: Accelerating the Rate of Astronomical Discovery

    NASA Astrophysics Data System (ADS)

    Norris, Ray P.

    2010-11-01

    Special Session 5 on Accelerating the Rate of Astronomical Discovery addressed a range of potential limits to progress: paradigmatic, technological, organizational, and political. It examined each issue both from modern and historical perspectives, and drew lessons to guide future progress. A number of issues were identified which may regulate the flow of discoveries, such as the balance between large strongly-focussed projects and instruments, designed to answer the most fundamental questions confronting us, and the need to maintain a creative environment with room for unorthodox thinkers and bold, high risk, projects. Also important is the need to maintain historical and cultural perspectives, and the need to engage the minds of the most brilliant young people on the planet, regardless of their background, ethnicity, gender, or geography.

  17. A model to calculate the induced dose rate around an 18 MV ELEKTA linear accelerator.

    PubMed

    Perrin, Bruce; Walker, Anne; Mackay, Ranald

    2003-03-01

    The dose rate due to activity induced by (gamma, n) reactions around an ELEKTA Precise accelerator running at 18 MV is reported. A model to calculate the induced dose rate for a variety of working practices has been derived and compared to the measured values. From this model, the dose received by the staff using the machine can be estimated. From measured dose rates at the face of the linear accelerator for a 10 x 10 cm2 jaw setting at 18 MV an activation coefficient per MU was derived for each of the major activation products. The relative dose rates at points around the linac head, for different energy and jaw settings, were measured. Dose rates adjacent to the patient support system and portal imager were also measured. A model to calculate the dose rate at these points was derived, and compared to those measured over a typical working week. The model was then used to estimate the maximum dose to therapists for the current working schedule on this machine. Calculated dose rates at the linac face agreed to within +/- 12% of those measured over a week, with a typical dose rate of 4.5 microSv h(-1) 2 min after the beam has stopped. The estimated maximum annual whole body dose for a treatment therapist, with the machine treating at only 18 MV, for 60000 MUs per week was 2.5 mSv. This compares well with value of 2.9 mSv published for a Clinac 21EX. A model has been derived to calculate the dose from the four dominant activation products of an ELEKTA Precise 18 MV linear accelerator. This model is a useful tool to calculate the induced dose rate around the treatment head. The model can be used to estimate the dose to the staff for typical working patterns. PMID:12696804

  18. GPU accelerated processing of astronomical high frame-rate videosequences

    NASA Astrophysics Data System (ADS)

    Vítek, Stanislav; Švihlík, Jan; Krasula, Lukáš; Fliegel, Karel; Páta, Petr

    2015-09-01

    Astronomical instruments located around the world are producing an incredibly large amount of possibly interesting scientific data. Astronomical research is expanding into large and highly sensitive telescopes. Total volume of data rates per night of operations also increases with the quality and resolution of state-of-the-art CCD/CMOS detectors. Since many of the ground-based astronomical experiments are placed in remote locations with limited access to the Internet, it is necessary to solve the problem of the data storage. It mostly means that current data acquistion, processing and analyses algorithm require review. Decision about importance of the data has to be taken in very short time. This work deals with GPU accelerated processing of high frame-rate astronomical video-sequences, mostly originating from experiment MAIA (Meteor Automatic Imager and Analyser), an instrument primarily focused to observing of faint meteoric events with a high time resolution. The instrument with price bellow 2000 euro consists of image intensifier and gigabite ethernet camera running at 61 fps. With resolution better than VGA the system produces up to 2TB of scientifically valuable video data per night. Main goal of the paper is not to optimize any GPU algorithm, but to propose and evaluate parallel GPU algorithms able to process huge amount of video-sequences in order to delete all uninteresting data.

  19. Comparative Aggregate Patterns of Grade Retention Rates.

    ERIC Educational Resources Information Center

    Morris, Don R.

    A search for patterns in grade retention rates across grades 1-12 to construct simulation research models is described in this paper. Aggregate data from Shepard and Smith (1989) on grade retention rates from 12 American states for the year 1979-80 and from 11 states for 1985-86 were examined for across-grade patterns, supplemented by Dade County…

  20. DnaK-Dependent Accelerated Evolutionary Rate in Prokaryotes.

    PubMed

    Kadibalban, A Samer; Bogumil, David; Landan, Giddy; Dagan, Tal

    2016-01-01

    Many proteins depend on an interaction with molecular chaperones in order to fold into a functional tertiary structure. Previous studies showed that protein interaction with the GroEL/GroES chaperonine and Hsp90 chaperone can buffer the impact of slightly deleterious mutations in the protein sequence. This capacity of GroEL/GroES to prevent protein misfolding has been shown to accelerate the evolution of its client proteins. Whether other bacterial chaperones have a similar effect on their client proteins is currently unknown. Here, we study the impact of DnaK (Hsp70) chaperone on the evolution of its client proteins. Evolutionary parameters were derived from comparison of the Escherichia coli proteome to 1,808,565 orthologous proteins in 1,149 proteobacterial genomes. Our analysis reveals a significant positive correlation between protein binding frequency with DnaK and evolutionary rate. Proteins with high binding affinity to DnaK evolve on average 4.3-fold faster than proteins in the lowest binding affinity class at the genus resolution. Differences in evolutionary rates of DnaK interactor classes are still significant after adjusting for possible effects caused by protein expression level. Furthermore, we observe an additive effect of DnaK and GroEL chaperones on the evolutionary rates of their common interactors. Finally, we found pronounced similarities in the physicochemical profiles that characterize proteins belonging to DnaK and GroEL interactomes. Our results thus implicate DnaK-mediated folding as a major component in shaping protein evolutionary dynamics in bacteria and supply further evidence for the long-term manifestation of chaperone-mediated folding on genome evolution. PMID:27189986

  1. DnaK-Dependent Accelerated Evolutionary Rate in Prokaryotes

    PubMed Central

    Kadibalban, A. Samer; Bogumil, David; Landan, Giddy; Dagan, Tal

    2016-01-01

    Many proteins depend on an interaction with molecular chaperones in order to fold into a functional tertiary structure. Previous studies showed that protein interaction with the GroEL/GroES chaperonine and Hsp90 chaperone can buffer the impact of slightly deleterious mutations in the protein sequence. This capacity of GroEL/GroES to prevent protein misfolding has been shown to accelerate the evolution of its client proteins. Whether other bacterial chaperones have a similar effect on their client proteins is currently unknown. Here, we study the impact of DnaK (Hsp70) chaperone on the evolution of its client proteins. Evolutionary parameters were derived from comparison of the Escherichia coli proteome to 1,808,565 orthologous proteins in 1,149 proteobacterial genomes. Our analysis reveals a significant positive correlation between protein binding frequency with DnaK and evolutionary rate. Proteins with high binding affinity to DnaK evolve on average 4.3-fold faster than proteins in the lowest binding affinity class at the genus resolution. Differences in evolutionary rates of DnaK interactor classes are still significant after adjusting for possible effects caused by protein expression level. Furthermore, we observe an additive effect of DnaK and GroEL chaperones on the evolutionary rates of their common interactors. Finally, we found pronounced similarities in the physicochemical profiles that characterize proteins belonging to DnaK and GroEL interactomes. Our results thus implicate DnaK-mediated folding as a major component in shaping protein evolutionary dynamics in bacteria and supply further evidence for the long-term manifestation of chaperone-mediated folding on genome evolution. PMID:27189986

  2. The temporal relationship between infant heart rate acceleration and crying in an aversive situation.

    PubMed

    Vaughn, B; Sroufe, L A

    1979-06-01

    The temporal relationship between heart rate (HR) acceleration and crying was examined in 16 8-16-month-old infants. Consistently, the HR acceleration began well before the onset of crying, suggesting that such acceleration is not merely a by-product of crying. The accelerations observed were above and beyond a return to baseline following orienting. The crying itself validates the association between these instances of HR acceleration and negative effect. PMID:487890

  3. Comparative study of medium damped and detuned linear accelerator structures

    SciTech Connect

    Jean-Francois Ostiguy et al.

    2001-08-22

    Long range wakefields are a serious concern for a future linear collider based on room temperature accelerating structures. They can be suppressed either by detuning and or local damping or with some combination of both strategies. Detuning relies on precisely phasing the contributions of the dipole modes excited by the passage of a single bunch. This is accomplished by controlling individual mode frequencies, a process which dictates individual cell dimensional tolerances. Each mode must be excited with the correct strength; this in turn, determines cell-to-cell alignment tolerances. In contrast, in a locally damped structure, the modes are attenuated at the cell level. Clearly, mode frequencies and relative excitation become less critical in that context; mechanical fabrication tolerances can be relaxed. While local damping is ideal from the stand-point of long range wakefield suppression, this comes at the cost of reducing the shunt impedance and possibly unacceptable localized heating. Recently, the Medium Damped Structure (MDS), a compromise between detuning and local damping, has generated some interest. In this paper, we compare a hypothetical MDS to the NLC Rounded Damped Detuned Structure (RDDS) and investigate possible advantages from the standpoint fabrication tolerances and their relation to beam stability and emittance preservation.

  4. Voltage stress effects on microcircuit accelerated life test failure rates

    NASA Technical Reports Server (NTRS)

    Johnson, G. M.

    1976-01-01

    The applicability of Arrhenius and Eyring reaction rate models for describing microcircuit aging characteristics as a function of junction temperature and applied voltage was evaluated. The results of a matrix of accelerated life tests with a single metal oxide semiconductor microcircuit operated at six different combinations of temperature and voltage were used to evaluate the models. A total of 450 devices from two different lots were tested at ambient temperatures between 200 C and 250 C and applied voltages between 5 Vdc and 15 Vdc. A statistical analysis of the surface related failure data resulted in bimodal failure distributions comprising two lognormal distributions; a 'freak' distribution observed early in time, and a 'main' distribution observed later in time. The Arrhenius model was shown to provide a good description of device aging as a function of temperature at a fixed voltage. The Eyring model also appeared to provide a reasonable description of main distribution device aging as a function of temperature and voltage. Circuit diagrams are shown.

  5. Effect of acceleration rate on automatic transmission shift-speeds for two 1979 Novas. Technical report

    SciTech Connect

    Jones, R.

    1980-01-01

    Variations in acceleration rates will result in variations in vehicle fuel economy. If typical vehicle acceleration rates are distributed in the same manner as the accelerations are distributed on the EPA test cycles, or if the vehicle operational characteristics do not significantly change with acceleration rate, then results from the EPA cycles should be representative of average vehicle use. However, if vehicle operational characteristics change with changing acceleration rates, and if vehicle accelerations in consumer use are not distributed in the same manner as the accelerations of the EPA test cycle, then significant differences between EPA estimated fuel economy and actual vehicle fuel consumption may result. One vehicle characteristic which often changes with acceleration rate is the transmission shift speed for vehicles with automatic transmissions. To determine the effects of acceleration rates on transmission shift speeds, EPA recently conducted a short test sequence on two vehicles with automatic transmissions. These tests determined the relation between vehicle acceleration rate and transmission shift speed for acceleration rates from 1 to 6 mph/sec.

  6. The origin of modern frogs (Neobatrachia) was accompanied by acceleration in mitochondrial and nuclear substitution rates

    PubMed Central

    2012-01-01

    Background Understanding the causes underlying heterogeneity of molecular evolutionary rates among lineages is a long-standing and central question in evolutionary biology. Although several earlier studies showed that modern frogs (Neobatrachia) experienced an acceleration of mitochondrial gene substitution rates compared to non-neobatrachian relatives, no further characterization of this phenomenon was attempted. To gain new insights on this topic, we sequenced the complete mitochondrial genomes and nine nuclear loci of one pelobatoid (Pelodytes punctatus) and five neobatrachians, Heleophryne regis (Heleophrynidae), Lechriodus melanopyga (Limnodynastidae), Calyptocephalella gayi (Calyptocephalellidae), Telmatobius bolivianus (Ceratophryidae), and Sooglossus thomasseti (Sooglossidae). These represent major clades not included in previous mitogenomic analyses, and most of them are remarkably species-poor compared to other neobatrachians. Results We reconstructed a fully resolved and robust phylogeny of extant frogs based on the new mitochondrial and nuclear sequence data, and dated major cladogenetic events. The reconstructed tree recovered Heleophryne as sister group to all other neobatrachians, the Australasian Lechriodus and the South American Calyptocephalella formed a clade that was the sister group to Nobleobatrachia, and the Seychellois Sooglossus was recovered as the sister group of Ranoides. We used relative-rate tests and direct comparison of branch lengths from mitochondrial and nuclear-based trees to demonstrate that both mitochondrial and nuclear evolutionary rates are significantly higher in all neobatrachians compared to their non-neobatrachian relatives, and that such rate acceleration started at the origin of Neobatrachia. Conclusions Through the analysis of the selection coefficient (ω) in different branches of the tree, we found compelling evidence of relaxation of purifying selection in neobatrachians, which could (at least in part) explain the

  7. The Temporal Relationship between Infant Heart Rate Acceleration and Crying in an Aversive Situation.

    ERIC Educational Resources Information Center

    Vaughn, Brian; Sroufe, L. Alan

    1979-01-01

    Shows that the heart rate acceleration of 16 infants ranging in age from 8 to 16 months consistently began well before the onset of crying. This suggests that heart rate acceleration is not merely a by-product of crying but that it is associated with negative affect. (JMB)

  8. Effects of propellant composition variables on acceleration-induced burning-rate augmentation of solid propellants

    NASA Technical Reports Server (NTRS)

    Northam, G. B.

    1972-01-01

    This work was conducted to define further the effects of propellant composition variables on the acceleration-induced burning rate augmentation of solid propellants. The rate augmentation at a given acceleration was found to be a nonlinear inverse function of the reference burning rate and not controlled by binder or catalyst type at a given reference rate. A nonaluminized propellant and a low rate double-base propellant exhibited strong transient rate augmentation due to surface pitting resulting from the retention of hot particles on the propellant surface.

  9. Reaction Rate Acceleration and Tg Depression of Polycyanurate Under Nanopore Confinement

    NASA Astrophysics Data System (ADS)

    Lopez, Evelyn; Simon, Sindee L.

    2015-03-01

    Material properties such as Tg and the reaction kinetics are known to deviate from the bulk when subjected to nano-sized confinement. Previous work from our laboratory on the trimerization of cyanate esters found that the reaction kinetics were faster for a monofunctional reactant compared to a difunctional monomer, whereas the Tg depression was greater for the crosslinked product of the latter compared to the low molecular weight trimer of the former. The origin of the changes in nanoconfined reaction rates differs from those that govern changes in the Tg. The research objective is to further explore the effect that confinement has on reaction kinetics and Tg using a mixture consisting of mono- and di- cyanate ester monomers. The product is an uncrosslinked polycyanurate with Mn = 5240 g/mol and PDI = 1.78. The confinement mediums are controlled pore glasses with diameters ranging from 8.1 to 111.1 nm. The nanopore-confined material was synthesized in-situ and the reaction kinetics are followed by DSC; after the reaction, the Tg values of the nanoconfined polymer where also measured by DSC. An acceleration factor of 13 and a Tg depression of 38 °C are observed for the material confined in the smallest 8.1 nm-diameter pores. The Tg depression is between those of the trimer and network previously studied, while the acceleration of the reaction rate is lower. Our results are consistent with the reaction acceleration arising from packing effects at the pore wall and the Tg depression arising from intrinsic size effects.

  10. Near-term acceleration in the rate of temperature change

    NASA Astrophysics Data System (ADS)

    Smith, Steven J.; Edmonds, James; Hartin, Corinne A.; Mundra, Anupriya; Calvin, Katherine

    2015-04-01

    Anthropogenically driven climate changes, which are expected to impact human and natural systems, are often expressed in terms of global-mean temperature. The rate of climate change over multi-decadal scales is also important, with faster rates of change resulting in less time for human and natural systems to adapt. We find that present trends in greenhouse-gas and aerosol emissions are now moving the Earth system into a regime in terms of multi-decadal rates of change that are unprecedented for at least the past 1,000 years. The rate of global-mean temperature increase in the CMIP5 (ref. ) archive over 40-year periods increases to 0.25 +/- 0.05 °C (1σ) per decade by 2020, an average greater than peak rates of change during the previous one to two millennia. Regional rates of change in Europe, North America and the Arctic are higher than the global average. Research on the impacts of such near-term rates of change is urgently needed.

  11. Near-Term Acceleration In The Rate of Temperature Change

    SciTech Connect

    Smith, Steven J.; Edmonds, James A.; Hartin, Corinne A.; Mundra, Anupriya; Calvin, Katherine V.

    2015-03-09

    Anthropogenically-driven climate changes, which are expected to impact human and natural systems, are often expressed in terms of global-mean temperature . The rate of climate change over multi-decadal scales is also important, with faster rates of change resulting in less time for human and natural systems to adapt . We find that current trends in greenhouse gas and aerosol emissions are now moving the Earth system into a regime in terms of multi-decadal rates of change that are unprecedented for at least the last 1000 years. The rate of global-mean temperature increase in the CMIP5 archive over 40-year periods increases to 0.25±0.05 (1σ) °C per decade by 2020, an average greater than peak rates of change during the previous 1-2 millennia. Regional rates of change in Europe, North America and the Arctic are higher than the global average. Research on the impacts of such near-term rates of change is urgently needed.

  12. Framework for a Comparative Accelerated Testing Standard for PV Modules: Preprint

    SciTech Connect

    Kurtz, S.; Wohlgemuth, J.; Yamamichi, M.; Sample, T.; Miller, D.; Meakin, D.; Monokroussos, C.; TamizhMani, M.; Kempe, M.; Jordan, D.; Bosco, N.; Hacke, P.; Bermudez, V.; Kondo, M.

    2013-08-01

    As the photovoltaic industry has grown, the interest in comparative accelerated testing has also grown. Private test labs offer testing services that apply greater stress than the standard qualification tests as tools for differentiating products and for gaining increased confidence in long-term PV investments. While the value of a single international standard for comparative accelerated testing is widely acknowledged, the development of a consensus is difficult. This paper strives to identify a technical basis for a comparative standard.

  13. Fundamental difference of subpicosecond laser interaction compared to longer pulses for ultrahigh acceleration

    SciTech Connect

    Foeldes, I. B.; Lalousis, P.; Moustaizis, S.; Hora, H.

    2012-07-09

    Interaction of picosecond laser pulses above terawatt power with high density plasmas shows a nearly 100% conversion of the laser energy into directed acceleration of the electron cloud by nonlinear (ponderomotive) forces giving the ion cloud accelerations several orders of magnitude higher than comparable nanosecond interaction based on thermal pressure processes.

  14. Mortality rate acceleration and post-reproductive lifespan in matrilineal whale species.

    PubMed

    Foote, Andrew D

    2008-04-23

    The strength of selection to increase the span of a life stage is dependent upon individuals at that stage being able to contribute towards individual fitness and the probability of their surviving to that stage. Complete reproductive cessation and a long post-reproductive female lifespan as found in humans are also found in killer whale (Orcinus orca) and short-finned pilot whale (Globicephala macrorhynchus), but not in the long-finned pilot whale (Globicephala melaena). Each species forms kin-based, stable matrilineal groups and exhibits kin-directed behaviours that could increase inclusive fitness. Here, the initial mortality rate and mortality rate-doubling time of females of these three closely related whale species are compared. The initial mortality rate shows little variation among pilot whale species; however mortality rate accelerates almost twice as fast in the long-finned pilot whale as it does in killer whale and short-finned pilot whale. Selection for a long post-reproductive female lifespan in matrilineal whales may therefore be determined by the proportion of females surviving past the point of reproductive cessation. PMID:18252662

  15. International PV QA Task Force's Proposed Comparative Rating System for PV Modules: Preprint

    SciTech Connect

    Wohlgemuth, J.; Kurtz, S.

    2014-10-01

    The International PV Quality Assurance Task Force is developing a rating system that provides comparative information about the relative durability of PV modules. Development of accelerated stress tests that can provide such comparative information is seen as a major step toward being able to predict PV module service life. This paper will provide details of the ongoing effort to determine the format of such an overall module rating system. The latest proposal is based on using three distinct climate zones as defined in IEC 60721-2-1 for two different mounting systems. Specific stresses beyond those used in the qualification tests are being developed for each of the selected climate zones.

  16. Comparing humans to automation in rating photographic aesthetics

    NASA Astrophysics Data System (ADS)

    Kakarala, Ramakrishna; Agrawal, Abhishek; Morales, Sandino

    2015-03-01

    Computer vision researchers have recently developed automated methods for rating the aesthetic appeal of a photograph. Machine learning techniques, applied to large databases of photos, mimic with reasonably good accuracy the mean ratings of online viewers. However, owing to the many factors underlying aesthetics, it is likely that such techniques for rating photos do not generalize well beyond the data on which they are trained. This paper reviews recent attempts to compare human ratings, obtained in a controlled setting, to ratings provided by machine learning techniques. We review methods to obtain meaningful ratings both from selected groups of judges and also from crowd sourcing. We find that state-of-the-art techniques for automatic aesthetic evaluation are only weakly correlated with human ratings. This shows the importance of obtaining data used for training automated systems under carefully controlled conditions.

  17. Comparable stocks, boundedly rational stock markets and IPO entry rates.

    PubMed

    Chok, Jay; Qian, Jifeng

    2013-01-01

    In this study, we examine how initial public offerings (IPO) entry rates are affected when stock markets are boundedly rational and IPO firms infer information from their counterparts in the market. We hypothesize a curvilinear relationship between the number of comparable stocks and initial public offerings (IPO) entry rates into the NASDAQ Stock Exchange. Furthermore, we argue that trading volume and changes in stock returns partially mediates the relationship between the number of comparable stocks and IPO entry rates. The statistical evidence provides strong support for the hypotheses. PMID:23690924

  18. Comparable Stocks, Boundedly Rational Stock Markets and IPO Entry Rates

    PubMed Central

    Chok, Jay; Qian, Jifeng

    2013-01-01

    In this study, we examine how initial public offerings (IPO) entry rates are affected when stock markets are boundedly rational and IPO firms infer information from their counterparts in the market. We hypothesize a curvilinear relationship between the number of comparable stocks and initial public offerings (IPO) entry rates into the NASDAQ Stock Exchange. Furthermore, we argue that trading volume and changes in stock returns partially mediates the relationship between the number of comparable stocks and IPO entry rates. The statistical evidence provides strong support for the hypotheses. PMID:23690924

  19. The rate of change of acceleration: implications to head kinematics during rear-end impacts.

    PubMed

    Hynes, Loriann M; Dickey, James P

    2008-05-01

    Whiplash is a mechanism of injury commonly associated with rear-impact vehicle collisions. To date, research has focused primarily on changes in velocity and acceleration as key factors for determining injuries due to whiplash mechanisms, but other characteristics of the acceleration pulse may be important. This study assessed whether the head acceleration response to whiplash-like perturbation profiles were affected by a change in the rate of the applied acceleration, or jerk. Twenty-one subjects were exposed to different low-velocity rear-impact whiplash-like perturbations using a precisely controlled robotic platform. The perturbations were divided into two groupings of peak acceleration (approximately 10 (high) and 5.7 (low) m/s2) and three groupings of jerk (approximately 260, 310, and 360 m/s3). These six profiles were repeated twice. Results demonstrated that the jerk magnitude significantly affected forehead acceleration in the vertical and horizontal directions. Increasing the magnitude of the platform acceleration also differentially affected the horizontal and vertical forehead accelerations. This indicates that the level of jerk influences the resulting head kinematics and should be considered when designing or interpreting experiments that are attempting to predict injury from whiplash-like perturbations. PMID:18460374

  20. Accelerated forgetting? An evaluation on the use of long-term forgetting rates in patients with memory problems

    PubMed Central

    Geurts, Sofie; van der Werf, Sieberen P.; Kessels, Roy P. C.

    2015-01-01

    The main focus of this review was to evaluate whether long-term forgetting rates (delayed tests, days, to weeks, after initial learning) are more sensitive measures than standard delayed recall measures to detect memory problems in various patient groups. It has been suggested that accelerated forgetting might be characteristic for epilepsy patients, but little research has been performed in other populations. Here, we identified eleven studies in a wide range of brain injured patient groups, whose long-term forgetting patterns were compared to those of healthy controls. Signs of accelerated forgetting were found in three studies. The results of eight studies showed normal forgetting over time for the patient groups. However, most of the studies used only a recognition procedure, after optimizing initial learning. Based on these results, we recommend the use of a combined recall and recognition procedure to examine accelerated forgetting and we discuss the relevance of standard and optimized learning procedures in clinical practice. PMID:26106343

  1. Accelerated forgetting? An evaluation on the use of long-term forgetting rates in patients with memory problems.

    PubMed

    Geurts, Sofie; van der Werf, Sieberen P; Kessels, Roy P C

    2015-01-01

    The main focus of this review was to evaluate whether long-term forgetting rates (delayed tests, days, to weeks, after initial learning) are more sensitive measures than standard delayed recall measures to detect memory problems in various patient groups. It has been suggested that accelerated forgetting might be characteristic for epilepsy patients, but little research has been performed in other populations. Here, we identified eleven studies in a wide range of brain injured patient groups, whose long-term forgetting patterns were compared to those of healthy controls. Signs of accelerated forgetting were found in three studies. The results of eight studies showed normal forgetting over time for the patient groups. However, most of the studies used only a recognition procedure, after optimizing initial learning. Based on these results, we recommend the use of a combined recall and recognition procedure to examine accelerated forgetting and we discuss the relevance of standard and optimized learning procedures in clinical practice. PMID:26106343

  2. Comparative mitochondrial genomics of snakes: extraordinary substitution rate dynamics and functionality of the duplicate control region

    PubMed Central

    Jiang, Zhi J; Castoe, Todd A; Austin, Christopher C; Burbrink, Frank T; Herron, Matthew D; McGuire, Jimmy A; Parkinson, Christopher L; Pollock, David D

    2007-01-01

    Background The mitochondrial genomes of snakes are characterized by an overall evolutionary rate that appears to be one of the most accelerated among vertebrates. They also possess other unusual features, including short tRNAs and other genes, and a duplicated control region that has been stably maintained since it originated more than 70 million years ago. Here, we provide a detailed analysis of evolutionary dynamics in snake mitochondrial genomes to better understand the basis of these extreme characteristics, and to explore the relationship between mitochondrial genome molecular evolution, genome architecture, and molecular function. We sequenced complete mitochondrial genomes from Slowinski's corn snake (Pantherophis slowinskii) and two cottonmouths (Agkistrodon piscivorus) to complement previously existing mitochondrial genomes, and to provide an improved comparative view of how genome architecture affects molecular evolution at contrasting levels of divergence. Results We present a Bayesian genetic approach that suggests that the duplicated control region can function as an additional origin of heavy strand replication. The two control regions also appear to have different intra-specific versus inter-specific evolutionary dynamics that may be associated with complex modes of concerted evolution. We find that different genomic regions have experienced substantial accelerated evolution along early branches in snakes, with different genes having experienced dramatic accelerations along specific branches. Some of these accelerations appear to coincide with, or subsequent to, the shortening of various mitochondrial genes and the duplication of the control region and flanking tRNAs. Conclusion Fluctuations in the strength and pattern of selection during snake evolution have had widely varying gene-specific effects on substitution rates, and these rate accelerations may have been functionally related to unusual changes in genomic architecture. The among-lineage and

  3. Accounting for rate variation among lineages in comparative demographic analyses

    USGS Publications Warehouse

    Hope, Andrew G.; Ho, Simon Y. W.; Malaney, Jason L.; Cook, Joseph A.; Talbot, Sandra L.

    2014-01-01

    Genetic analyses of contemporary populations can be used to estimate the demographic histories of species within an ecological community. Comparison of these demographic histories can shed light on community responses to past climatic events. However, species experience different rates of molecular evolution, and this presents a major obstacle to comparative demographic analyses. We address this problem by using a Bayesian relaxed-clock method to estimate the relative evolutionary rates of 22 small mammal taxa distributed across northwestern North America. We found that estimates of the relative molecular substitution rate for each taxon were consistent across the range of sampling schemes that we compared. Using three different reference rates, we rescaled the relative rates so that they could be used to estimate absolute evolutionary timescales. Accounting for rate variation among taxa led to temporal shifts in our skyline-plot estimates of demographic history, highlighting both uniform and idiosyncratic evolutionary responses to directional climate trends for distinct ecological subsets of the small mammal community. Our approach can be used in evolutionary analyses of populations from multiple species, including comparative demographic studies.

  4. Comparing Audio and Video Data for Rating Communication

    PubMed Central

    Williams, Kristine; Herman, Ruth; Bontempo, Daniel

    2013-01-01

    Video recording has become increasingly popular in nursing research, adding rich nonverbal, contextual, and behavioral information. However, benefits of video over audio data have not been well established. We compared communication ratings of audio versus video data using the Emotional Tone Rating Scale. Twenty raters watched video clips of nursing care and rated staff communication on 12 descriptors that reflect dimensions of person-centered and controlling communication. Another group rated audio-only versions of the same clips. Interrater consistency was high within each group with ICC (2,1) for audio = .91, and video = .94. Interrater consistency for both groups combined was also high with ICC (2,1) for audio and video = .95. Communication ratings using audio and video data were highly correlated. The value of video being superior to audio recorded data should be evaluated in designing studies evaluating nursing care. PMID:23579475

  5. Diffusion Rates on the Overhead Projector: Amines Compared to HCl.

    ERIC Educational Resources Information Center

    Solomon, Sally; And Others

    1996-01-01

    Describes a method to compare diffusion rates of selected amines to that of HCl. Provides an opportunity to introduce simple organic compounds early in the general chemistry curriculum and can be used to test Graham's Law for several different molar masses. (JRH)

  6. Economists Concoct New Method for Comparing Graduation Rates

    ERIC Educational Resources Information Center

    Glenn, David

    2007-01-01

    A pair of economists at the College of William and Mary have devised a new way of comparing colleges' graduation rates--a method, borrowed from business analysis, that they believe is fairer and more useful than the techniques used by "U.S. News & World Report" and the Education Trust. That general technique of regression analysis underlies the…

  7. Wage Rate Comparability Review Washington State Work Study Program.

    ERIC Educational Resources Information Center

    Washington State Higher Education Coordinating Board, Olympia.

    Washington State's Higher Education Coordinating Board undertook a review of the State Work Study (SWS) program requirements related to the classification and compensation of SWS positions at public colleges and universities. A task force studying wage rate comparability was convened to review statutory directives related to this issue and to…

  8. Effects of normal acceleration on transient burning rate augmentation of an aluminized solid propellant

    NASA Technical Reports Server (NTRS)

    Northam, G. B.

    1972-01-01

    Instantaneous burning rate data for a polybutadiene acrylic acid propellant, containing 16 weight percent aluminum, were calculated from the pressure histories of a test motor with 96.77 sq cm of burning area and a 5.08-cm-thick propellant web. Additional acceleration tests were conducted with reduced propellant web thicknesses of 3.81, 2.54, and 1.27 cm. The metallic residue collected from the various web thickness tests was characterized by weight and shape and correlated with the instantaneous burning rate measurements. Rapid depressurization extinction tests were conducted in order that surface pitting characteristics due to localized increased burning rate could be correlated with the residue analysis and the instantaneous burning rate data. The acceleration-induced burning rate augmentation was strongly dependent on propellant distance burned, or burning time, and thus was transient in nature. The results from the extinction tests and the residue analyses indicate that the transient rate augmentation was highly dependent on local enhancement of the combustion zone heat feedback to the surface by the growth of molten residue particles on or just above the burning surface. The size, shape, and number density of molten residue particles, rather than the total residue weight, determined the acceleration-induced burning rate augmentation.

  9. Accelerating rate calorimetry: A new technique for safety studies in lithium systems

    NASA Technical Reports Server (NTRS)

    Ebner, W. B.

    1982-01-01

    The role of exothermic reactions in battery test modes is discussed. The exothermic reactions are characterized with respect to their time-temperature and time-pressure behavior. Reactions occuring for any major exotherm were examined. The accelerating rate calorimetry methods was developed to study lithium cells susceptibility to thermal runaway reactions following certain abuse modes such as forced discharge into reversal and charging.

  10. Deceleration and acceleration capacities of heart rate associated with heart failure with high discriminating performance

    PubMed Central

    Hu, Wei; Jin, Xian; Zhang, Peng; Yu, Qiang; Yin, Guizhi; Lu, Yi; Xiao, Hongbing; Chen, Yueguang; Zhang, Dadong

    2016-01-01

    Accurate measurements of autonomic nerve regulation in heart failure (HF) were unresolved. The discriminating performance of deceleration and acceleration capacities of heart rate in HF was evaluated in 130 HF patients and 212 controls. Acceleration capacity and deceleration capacity were independent risk factors for HF in males, evaluated by multiple logistic regression analysis, with odds ratios (ORs) of 5.94 and 0.13, respectively. Acceleration capacity was also an independent risk factor for HF in females, with an OR of 8.58. Deceleration capacity was the best cardiac electrophysiological index to classify HF in males, with an area under the receiver operating characteristic curve (AUC) of 0.88. Deceleration capacity was the best classification factor of HF in females with an AUC of 0.97, significantly higher than even left ventricular ejection fraction (LVEF). Acceleration capacity also showed high performance in classifying HF in males (0.84) and females (0.92). The cut-off values of deceleration capacity for HF classification in males and females were 4.55 ms and 4.85 ms, respectively. The cut-off values of acceleration capacity for HF classification in males and females were −6.15 ms and −5.75 ms, respectively. Our study illustrates the role of acceleration and deceleration capacity measurements in the neuro-pathophysiology of HF. PMID:27005970

  11. Comparing Trends in Cancer Rates Across Overlapping Regions

    PubMed Central

    Li, Yi; Tiwari, Ram C.

    2008-01-01

    Monitoring and comparing trends in cancer rates across geographic regions or over different time periods has been one main task of the National Cancer Institute (NCI) Surveillance, Epidemiology, and End Results (SEER) Program as it profiles health care quality as well as decides health care resource allocations within a spatial-temporal framework. A fundamental difficulty, however, arises when such comparisons have to be made for regions or time intervals that overlap, e.g. comparing the change in trends of mortality rates in a local area (e.g. the mortality rate of Breast Cancer in California) with a more global level (i.e. the national mortality rate of Breast Cancer). In view of sparsity of available methodologies, this paper develops a simple corrected Z-test that accounts for such overlapping. The performance of the proposed test over the two-sample “pooled” t-test that assumes independence across comparison groups is assessed via the Pitman asymptotic relative efficiency as well as Monte Carlo simulations and applications to the SEER cancer data. The proposed test will be important for the SEER*STAT software, maintained by the NCI, for the analysis of the SEER data. PMID:18371122

  12. Private Carriers' Physician Payment Rates Compared With Medicare and Medicaid.

    PubMed

    Krause, Trudy Millard; Ukhanova, Maria; Revere, Frances Lee

    2016-01-01

    This research evaluated the 2013 published physician reimbursement rates for Medicare and Medicaid in Texas and compared the rates with the mean fees from private carriers. Physician claims data were extracted from the Truven MarketScan Commercial Claims Databases. The average allowed amounts per unit per procedure code were compiled. The 2013 Medicare physician fee schedule was obtained and filtered to Texas. The 2013 Texas Medicaid physician fee schedule was obtained. The mean commercial allowed amounts were compared with those of Medicare and Medicaid on a per-unit rate. Comparison ratios were derived for each code. The CPT© procedure codes were then grouped into the categories assigned by the American Medical Association. The ratios of private/Medicare and private/Medicaid varied greatly by procedure type and locality, with the Texas Medicaid fees well below both private and Medicare fees. The discrepancy in payment amounts demonstrates the variation in payment rates among payer sources. The practical implications demonstrate the provider challenges in managing patient mix to maintain a viable practice. PMID:27295293

  13. Comparing Solar-Flare Acceleration of >-20 MeV Protons and Electrons Above Various Energies

    NASA Technical Reports Server (NTRS)

    Shih, Albert Y.

    2010-01-01

    A large fraction (up to tens of percent) of the energy released in solar flares goes into accelerated ions and electrons, and studies indicate that these two populations have comparable energy content. RHESSI observations have shown a striking close linear correlation between the 2.223 MeV neutron-capture gamma-ray line and electron bremsstrahlung emission >300 keV, indicating that the flare acceleration of >^20 MeV protons and >300 keV electrons is roughly proportional over >3 orders of magnitude in fluence. We show that the correlations of neutron-capture line fluence with GOES class or with bremsstrahlung emission at lower energies show deviations from proportionality, primarily for flares with lower fluences. From analyzing thirteen flares, we demonstrate that there appear to be two classes of flares with high-energy acceleration: flares that exhibit only proportional acceleration of ions and electrons down to 50 keV and flares that have an additional soft, low-energy bremsstrahlung component, suggesting two separate populations of accelerated electrons. We use RHESSI spectroscopy and imaging to investigate a number of these flares in detail.

  14. Charge Accretion Rate and Injection Radius of Ionized-Induced Injections in Laser Wakefield Accelerators

    NASA Astrophysics Data System (ADS)

    Zeng, Ming; Chen, Min; Sheng, Zheng-Ming

    2016-03-01

    Ionization-induced injection has recently been proved to be a stable injection method with several advantages in laser wakefield accelerators. However, the controlling of this injection process aiming at producing high quality electron beams is still challenging. In this paper, we examine the ionization injection processes and estimate the injection rate with two-dimensional particle-in-cell simulations. The injection rate is shown to increase linearly with the high-Z gas density as long as its ratio is smaller than some threshold in the mix gases. It is also shown that by changing the transverse mode of the driving lasers one can control the injection rate.

  15. Sensory Constraints on Birdsong Syntax: Neural Responses to Swamp Sparrow Songs with Accelerated Trill Rates

    PubMed Central

    Prather, JF; Peters, S; Mooney, R; Nowicki, S

    2013-01-01

    Both sensory and motor mechanisms can constrain behavioral performance. Sensory mechanisms may be especially important for constraining behaviors that depend on experience, such as learned birdsongs. Swamp sparrows learn to sing by imitating the song of a tutor, but sparrows fail to accurately imitate artificial tutor songs with abnormally accelerated trills, instead singing brief and rapid trills interrupted by silent gaps. This “broken syntax” has been proposed to arise from vocal-motor limitations. Here we consider whether sensory limitations exist that could also contribute to broken syntax. We tested this idea by recording auditory-evoked activity of sensorimotor neurons in the swamp sparrow’s brain that are known to be important for the learning, performance and perception of song. In freely behaving adult sparrows that sang songs with normal syntax, neurons were detected that exhibited precisely time-locked activity to each repetition of the syllable in a trill when presented at a natural rate. Those cells failed to faithfully follow syllables presented at an accelerated rate, however, and their failure to respond to consecutive syllables increased as a function of trill rate. This “flickering” auditory representation in animals performing normal syntax reveals a central constraint on the sensory processing of rapid trills. Furthermore, because these neurons are implicated in both song learning and perception, and because auditory flickering began to occur at accelerated trill rates previously associated with the emergence of broken song syntax, these sensory constraints may contribute to the emergence of broken syntax. PMID:23976787

  16. Childhood asthma utilization rates in a nonsmoking population of utah compared to state and national rates.

    PubMed

    Gren, Lisa H; Taylor, Brooke; Lyon, Joseph L

    2011-01-01

    Risk factors, such as parental smoking, are commonly associated with increased asthma symptoms and hospitalizations of children. Deseret Mutual Benefits Administrators (DMBA) is the health insurer for employees of The Church of Jesus Christ of Latter-day Saints and their families. Due to religious proscription, employees abstain from alcohol and tobacco use, creating a cohort of children not exposed to parental smoking. Calculation of hospitalization rates for DMBA, Utah, and the US were made in children to compare rates between a nonsmoking population and general populations. Compared to DMBA, rate ratios for asthma hospitalization and emergency department asthma visits were higher for the US and Utah. The incidence of hospital outpatient department and physician office visits was significantly greater for the US population compared to the DMBA. This study demonstrates a decreased need for health services used by children not exposed to second-hand smoke. PMID:22389787

  17. Ambient dose and dose rate measurements in the vicinity of Elekta Precise accelerators for radiation therapy.

    PubMed

    Zutz, H; Hupe, O

    2014-12-01

    In radiation therapy, commercially available medical linear accelerators (LINACs) are used. At high primary beam energies in the 10-MeV range, the leakage dose of the accelerator head and the backscatter from the room walls, the air and the patient become more important. Therefore, radiation protection measurements of photon dose rates in the treatment room and in the maze are performed to quantify the radiation field. Since the radiation of the LINACs is usually pulsed with short radiation pulse durations in the microsecond range, there are problems with electronic dose (rate) meters commonly used in radiation protection. In this paper measurements with ionisation chambers are presented and electronic dosemeters are used for testing at selected positions. The measured time-averaged dose rate ranges from a few microsieverts per hour in the maze to some millisieverts per hour in the vicinity of the accelerator head and up to some sieverts per hour in the blanked primary beam and several hundred sieverts per hour in the direct primary beam. PMID:24379437

  18. Comparative rates of evolution in endosymbiotic nuclear genomes

    PubMed Central

    Patron, Nicola J; Rogers, Matthew B; Keeling, Patrick J

    2006-01-01

    Background The nucleomorphs associated with secondary plastids of cryptomonads and chlorarachniophytes are the sole examples of organelles with eukaryotic nuclear genomes. Although not as widespread as their prokaryotic equivalents in mitochondria and plastids, nucleomorph genomes share similarities in terms of reduction and compaction. They also differ in several aspects, not least in that they encode proteins that target to the plastid, and so function in a different compartment from that in which they are encoded. Results Here, we test whether the phylogenetically distinct nucleomorph genomes of the cryptomonad, Guillardia theta, and the chlorarachniophyte, Bigelowiella natans, have experienced similar evolutionary pressures during their transformation to reduced organelles. We compared the evolutionary rates of genes from nuclear, nucleomorph, and plastid genomes, all of which encode proteins that function in the same cellular compartment, the plastid, and are thus subject to similar selection pressures. Furthermore, we investigated the divergence of nucleomorphs within cryptomonads by comparing G. theta and Rhodomonas salina. Conclusion Chlorarachniophyte nucleomorph genes have accumulated errors at a faster rate than other genomes within the same cell, regardless of the compartment where the gene product functions. In contrast, most nucleomorph genes in cryptomonads have evolved faster than genes in other genomes on average, but genes for plastid-targeted proteins are not overly divergent, and it appears that cryptomonad nucleomorphs are not presently evolving rapidly and have therefore stabilized. Overall, these analyses suggest that the forces at work in the two lineages are different, despite the similarities between the structures of their genomes. PMID:16772046

  19. The Formalism for Energy Changing Rate of an Accelerated Atom Coupled with Electromagnetic Vacuum Fluctuations

    NASA Astrophysics Data System (ADS)

    Zhang, Anwei

    2016-05-01

    The structure of the rate of variation of the atomic energy for an arbitrary stationary motion of the atom in interaction with a quantum electromagnetic field is investigated. Our main purpose is to rewrite the formalism in Zhu et al. (Phys Rev D 73:107501, 2006) and to deduce the general expressions of the Einstein A coefficients of an atom on an arbitrary stationary trajectory. The total rate of change of the energy and Einstein coefficients of the atom near a plate with finite temperature or acceleration are also investigated.

  20. Changes of deceleration and acceleration capacity of heart rate in patients with acute hemispheric ischemic stroke

    PubMed Central

    Xu, Yan-Hong; Wang, Xing-De; Yang, Jia-Jun; Zhou, Li; Pan, Yong-Chao

    2016-01-01

    Background and purpose Autonomic dysfunction is common after stroke, which is correlated with unfavorable outcome. Phase-rectified signal averaging is a newly developed technique for assessing cardiac autonomic function, by detecting sympathetic and vagal nerve activity separately through calculating acceleration capacity (AC) and deceleration capacity (DC) of heart rate. In this study, we used this technique for the first time to investigate the cardiac autonomic function of patients with acute hemispheric ischemic stroke. Methods A 24-hour Holter monitoring was performed in 63 patients with first-ever acute ischemic stroke in hemisphere and sinus rhythm, as well as in 50 controls with high risk of stroke. DC, AC, heart rate variability parameters, standard deviation of all normal-to-normal intervals (SDNN), and square root of the mean of the sum of the squares of differences between adjacent normal-to-normal intervals (RMSSD) were calculated. The National Institutes of Health Stroke Scale (NIHSS) was used to assess the severity of stroke. We analyzed the changes of DC, AC, SDNN, and RMSSD and also studied the correlations between these parameters and NIHSS scores. Results The R–R (R wave to R wave on electrocardiogram) intervals, DC, AC, and SDNN in the cerebral infarction group were lower than those in controls (P=0.003, P=0.002, P=0.006, and P=0.043), but the difference of RMSSD and the D-value and ratio between absolute value of AC (|AC|) and DC were not statistically significant compared with those in controls. The DC of the infarction group was significantly correlated with |AC|, SDNN, and RMSSD (r=0.857, r=0.619, and r=0.358; P=0.000, P=0.000, and P=0.004). Correlation analysis also showed that DC, |AC|, and SDNN were negatively correlated with NIHSS scores (r=−0.279, r=−0.266, and r=−0.319; P=0.027, P=0.035, and P=0.011). Conclusion Both DC and AC of heart rate decreased in patients with hemispheric infarction, reflecting a decrease in both vagal

  1. Application of convergence acceleration to the reactor kinetic equations: A comparative study

    SciTech Connect

    Picca, P.; Furfaro, R.; Ganapol, B. D.

    2013-07-01

    This presentation provides a comparison of two methodologies for the solution of reactor kinetic equations, namely for a standard finite difference and a semi-analytical approach. The above-mentioned methods are implemented in a convergence acceleration framework to enhance their efficiency and a comparative study is reported to verify whether it is more convenient to use a rudimentary but fast algorithm (finite difference) with respect to the more refined but computationally intense approach of the semi-analytical method. Performance on several test cases from the literature are compared. (authors)

  2. Artificial accelerators of the molecular chaperone Hsp90 facilitate rate-limiting conformational transitions.

    PubMed

    Zierer, Bettina K; Weiwad, Matthias; Rübbelke, Martin; Freiburger, Lee; Fischer, Gunter; Lorenz, Oliver R; Sattler, Michael; Richter, Klaus; Buchner, Johannes

    2014-11-01

    The molecular chaperone Hsp90 undergoes an ATP-driven cycle of conformational changes in which large structural rearrangements precede ATP hydrolysis. Well-established small-molecule inhibitors of Hsp90 compete with ATP-binding. We wondered whether compounds exist that can accelerate the conformational cycle. In a FRET-based screen reporting on conformational rearrangements in Hsp90 we identified compounds. We elucidated their mode of action and showed that they can overcome the intrinsic inhibition in Hsp90 which prevents these rearrangements. The mode of action is similar to that of the co-chaperone Aha1 which accelerates the Hsp90 ATPase. However, while the two identified compounds influence conformational changes, they target different aspects of the structural transitions. Also, the binding site determined by NMR spectroscopy is distinct. This study demonstrates that small molecules are capable of triggering specific rate-limiting transitions in Hsp90 by mechanisms similar to those in protein cofactors. PMID:25244159

  3. Error-Rate Estimation Based on Multi-Signal Flow Graph Model and Accelerated Radiation Tests.

    PubMed

    He, Wei; Wang, Yueke; Xing, Kefei; Deng, Wei; Zhang, Zelong

    2016-01-01

    A method of evaluating the single-event effect soft-error vulnerability of space instruments before launched has been an active research topic in recent years. In this paper, a multi-signal flow graph model is introduced to analyze the fault diagnosis and meantime to failure (MTTF) for space instruments. A model for the system functional error rate (SFER) is proposed. In addition, an experimental method and accelerated radiation testing system for a signal processing platform based on the field programmable gate array (FPGA) is presented. Based on experimental results of different ions (O, Si, Cl, Ti) under the HI-13 Tandem Accelerator, the SFER of the signal processing platform is approximately 10-3(error/particle/cm2), while the MTTF is approximately 110.7 h. PMID:27583533

  4. Modeling accelerated and decelerated drug release in terms of fractional release rate.

    PubMed

    Weiss, Michael

    2015-02-20

    The model of a proportional change in fractional dissolution rate was used to quantify influences on the vitro dissolution process. After fitting the original dissolution profile with an empirical model (inverse Gaussian distribution), acceleration and deceleration effects due to dissolution conditions or formulation parameters could be described by one parameter only. Acceleration of dissolution due to elevated temperature and deceleration by increasing the content of glyceryl monostearate in theophylline tablets are presented as examples. Likewise, this approach was applied to in vitro-in vivo correlation (IVIVC). It is shown that the model is appropriate when the plot of the in vivo versus in vivo times is nonlinear and can be described by a power function. The results demonstrate the utility of the model in dissolution testing and IVIVC assessment. PMID:25486334

  5. Phycocyanobilin accelerates liver regeneration and reduces mortality rate in carbon tetrachloride-induced liver injury mice

    PubMed Central

    Liu, Jie; Zhang, Qing-Yu; Yu, Li-Ming; Liu, Bin; Li, Ming-Yi; Zhu, Run-Zhi

    2015-01-01

    AIM: To investigate the hepatoprotective effects of phycocyanobilin (PCB) in reducing hepatic injury and accelerating hepatocyte proliferation following carbon tetrachloride (CCl4) treatment. METHODS: C57BL/6 mice were orally administered PCB 100 mg/kg for 4 d after CCl4 injection, and then the serum and liver tissue of the mice were collected at days 1, 2, 3, 5 and 7 after CCl4 treatment. A series of evaluations were performed to identify the curative effects on liver injury and recovery. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), albumin and superoxide dismutase (SOD) were detected to indirectly assess the anti-inflammatory effects of PCB. Meanwhile, we detected the expressions of hepatocyte growth factor, transforming growth factor alpha (TGF-α), TGF-β, tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), the factors which are associated with inflammation and liver regeneration. The protein expressions of proliferating cell nuclear antigen (PCNA), TNF-α and cytochrome C were detected by western blot. Furthermore, the survival rates were analyzed of mice which were administered a lethal dose of CCl4 (2.6 mg/kg) with or without PCB. RESULTS: In our research, PCB showed a strongly anti-inflammatory effect on CCl4-induced liver injury in mice. The ALT was significantly decreased after CCl4 treatment from day 1 (P < 0.01) and the AST was significantly decreased from day 2 (P < 0.001). Both albumin and liver SOD were increased from day 2 (P < 0.001 and P < 0.01), but serum SOD levels did not show a significant increase (P > 0.05). PCB protected the structure of liver from the injury by CCl4. TUNEL assay showed that PCB dramatically reduced the number of apoptotic cells after CCl4 treatment compared to the control (101.0 ± 25.4 vs 25.7 ± 6.4, P < 0.01). The result of western blotting showed that PCB could increase PCNA expression, decrease TNF-α and cytochrome C expression. Furthermore, data shows that PCB could improve the

  6. Accelerated Testing Methodology in Constant Stress-Rate Testing for Advanced Structural Ceramics: A Preloading Technique

    NASA Technical Reports Server (NTRS)

    Choi, Sung R.; Gyekenyesi, John P.; Huebert, Dean; Bartlett, Allen; Choi, Han-Ho

    2001-01-01

    Preloading technique was used as a means of an accelerated testing methodology in constant stress-rate (dynamic fatigue) testing for two different brittle materials. The theory developed previously for fatigue strength as a function of preload was further verified through extensive constant stress-rate testing for glass-ceramic and CRT glass in room temperature distilled water. The preloading technique was also used in this study to identify the prevailing failure mechanisms at elevated temperatures, particularly at lower test rates in which a series of mechanisms would be associated simultaneously with material failure, resulting in significant strength increase or decrease. Two different advanced ceramics including SiC whisker-reinforced composite silicon nitride and 96 wt% alumina were used at elevated temperatures. It was found that the preloading technique can be used as an additional tool to pinpoint the dominant failure mechanism that is associated with such a phenomenon of considerable strength increase or decrease.

  7. Accelerated Testing Methodology in Constant Stress-Rate Testing for Advanced Structural Ceramics: A Preloading Technique

    NASA Technical Reports Server (NTRS)

    Choi, Sung R.; Gyekenyesi, John P.; Huebert, Dean; Bartlett, Allen; Choi, Han-Ho

    2001-01-01

    Preloading technique was used as a means of an accelerated testing methodology in constant stress-rate ('dynamic fatigue') testing for two different brittle materials. The theory developed previously for fatigue strength as a function of preload was further verified through extensive constant stress-rate testing for glass-ceramic and CRT glass in room temperature distilled water. The preloading technique was also used in this study to identify the prevailing failure mechanisms at elevated temperatures, particularly at lower test rate in which a series of mechanisms would be associated simultaneously with material failure, resulting in significant strength increase or decrease. Two different advanced ceramics including SiC whisker-reinforced composite silicon nitride and 96 wt% alumina were used at elevated temperatures. It was found that the preloading technique can be used as an additional tool to pinpoint the dominant failure mechanism that is associated with such a phenomenon of considerable strength increase or decrease.

  8. Comparing infrared star formation rate indicators with optically derived quantities

    NASA Astrophysics Data System (ADS)

    Young, J. E.; Gronwall, C.; Salzer, J. J.; Rosenberg, J. L.

    2014-09-01

    We examine the UV reprocessing efficiencies of warm dust and polycyclic aromatic hydrocarbons (PAHs) through an analysis of the mid- and far-infrared surface luminosity densities of 85 nearby Hα-selected star-forming galaxies detected by the volume-limited KPNO (Kitt Peak National Observatory) International Spectroscopic Survey (KISS). Because Hα selection is not biased towards continuum-bright objects, the KISS sample spans a wide range in stellar masses (108-1012 M⊙), as well as Hα luminosity (1039-1043 erg s-1), mid-infrared 8.0 μm luminosity (1041-1044 erg s-1), and [Bw - R] colour (-0.1-2.2). We find that mid-infrared PAH emission in the Spitzer InfraRed Array Camera (IRAC) 8.0 μm band correlates with star formation, and that the efficiency with which galaxies reprocess UV energy into PAH emission depends on metallicity. We also find that the relationship between far-infrared luminosity in the Spitzer Multiband Imaging Photometer for Spitzer 24 μm band pass and Hα-measured star formation rate varies from galaxy to galaxy within our sample; we do not observe a metallicity dependence in this relationship. We use optical colours and established mass-to-light relationships to determine stellar masses for the KISS galaxies; we compare these masses to those of nearby galaxies as a confirmation that the volume-limited nature of KISS avoids strong biases. We also examine the relationship between IRAC 3.6 μm luminosity and galaxy stellar mass, and find a colour-dependent correlation between the two.

  9. Accelerated evolutionary rate in sulfur-oxidizing endosymbiotic bacteria associated with the mode of symbiont transmission.

    PubMed

    Peek, A S; Vrijenhoek, R C; Gaut, B S

    1998-11-01

    The nearly neutral theory of molecular evolution predicts that the rate of nucleotide substitution should accelerate in small populations at sites under low selective constraint. We examined these predictions with respect to the relative population sizes for three bacterial life histories within chemolithoautotrophic sulfur-oxidizing bacteria: (1) free-living bacteria, (2) environmentally captured symbionts, and (3) maternally transmitted symbionts. Both relative rates of nucleotide substitution and relative ratios of loop, stem, and domain substitutions from 1,165 nt of the small-subunit 16S rDNA were consistent with expectations of the nearly neutral theory. Relative to free-living sulfur-oxidizing autotrophic bacteria, the maternally transmitted symbionts have faster substitution rates overall and also in low-constraint domains of 16S rDNA. Nucleotide substitition rates also differ between loop and stem positions. All of these findings are consistent with the predictions that these symbionts have relatively small effective population sizes. In contrast, the rates of nucleotide substitution in environmentally captured symbionts are slower, particularly in high-constraint domains, than in free-living bacteria. PMID:12572615

  10. Canine fetal heart rate: do accelerations or decelerations predict the parturition day in bitches?

    PubMed

    Gil, E M U; Garcia, D A A; Giannico, A T; Froes, T R

    2014-10-15

    Ultrasonography is a safe and efficient technique for monitoring fetal development and viability. One of the most important and widely used parameters to verify fetal viability is the fetal heart rate (HR). In human medicine, the fetal HR normally oscillates during labor in transient accelerations and decelerations associated with uterine contractions. The present study investigated whether these variations also occur in canine fetuses and its relationship to parturition. A cohort study was conducted in 15 pregnant bitches undergoing two-dimensional high-resolution ultrasonographic examination during the 8th and 9th week of gestation. Fetal HR was assessed in M-mode for 5 minutes in each fetus in all bitches. In addition, the bitches were monitored for clinical signs of imminent parturition. Associations between the HR, antepartum time, and delivery characteristics were evaluated with a Poisson regression model. Fetal HR acceleration and deceleration occurred in canine fetuses and predicted the optimal time of parturition. These findings can help veterinarians and sonographers better understand this phenomenon in canine fetuses. PMID:24888684

  11. Appendix F: Comparing Beam Damage Rates Using Susceptibility Tables

    SciTech Connect

    Baer, Donald R.; Engelhard, Mark H.; Lea, Alan S.; Gaspar, Dan J.

    2003-11-01

    Many research groups have observed electron and x-ray damage on a variety of materials. It is, of course, highly desirable to take advantage of the considerable experience gained by others in observing the presence of damage. Ideally, damage processes and rates would be determined for the samples of interest on the instrument in which measurements are to be made. However, in many cases such measurements are not possible and many important speciments are one of a kind. Several compilations of damage rates are available in the literature 1,2, or from Companies 3. In most cases the data from these potentially useful data sets are not likely to directly relate to the damage rates that might be observed for other instruments. There are two related reasons for this. First there is over an order of magnitude difference between x-ray damage rates observed on instruments in current use, as reported by Yoshihara and Tanaka.4 In addition, many new instruments have higher x-ray fluxes than many older instruments. The damage rates observed in the Pacific Northwest National Laboratory (PNNL) PHI Quantum 2000, are in the lower 1/3 of the instruments reported in Reference 4 but are approximately 5 times faster than those reported by Beamson and Briggs1 in 1992 for the Scienta 300 system.

  12. Big Data and Comparative Effectiveness Research in Radiation Oncology: Synergy and Accelerated Discovery

    PubMed Central

    Trifiletti, Daniel M.; Showalter, Timothy N.

    2015-01-01

    Several advances in large data set collection and processing have the potential to provide a wave of new insights and improvements in the use of radiation therapy for cancer treatment. The era of electronic health records, genomics, and improving information technology resources creates the opportunity to leverage these developments to create a learning healthcare system that can rapidly deliver informative clinical evidence. By merging concepts from comparative effectiveness research with the tools and analytic approaches of “big data,” it is hoped that this union will accelerate discovery, improve evidence for decision making, and increase the availability of highly relevant, personalized information. This combination offers the potential to provide data and analysis that can be leveraged for ultra-personalized medicine and high-quality, cutting-edge radiation therapy. PMID:26697409

  13. Corn nitrogen fertilization rate tools compared over eight midwest states

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Publicly-available nitrogen (N) rate recommendation tools are utilized to help maximize yield in corn production. These tools often fail both when N is over-applied and result in excess N being lost to the environment, or when N is under-applied and the result in decreased yield and economic returns...

  14. Human microRNAs originated from two periods at accelerated rates in mammalian evolution.

    PubMed

    Iwama, Hisakazu; Kato, Kiyohito; Imachi, Hitomi; Murao, Koji; Masaki, Tsutomu

    2013-03-01

    MicroRNAs (miRNAs) are short, noncoding RNAs that modulate genes posttranscriptionally. Frequent gains and losses of miRNA genes have been reported to occur during evolution. However, little is known systematically about the periods of evolutionary origin of the present miRNA gene repertoire of an extant mammalian species. Thus, in this study, we estimated the evolutionary periods during which each of 1,433 present human miRNA genes originated within 15 periods, from human to platypus-human common ancestral branch and a class "conserved beyond theria," primarily using multiple genome alignments of 38 species, plus the pairwise genome alignments of five species. The results showed two peak periods in which the human miRNA genes originated at significantly accelerated rates. The most accelerated rate appeared in the period of the initial phase of hominoid lineage, and the second appeared shortly before Laurasiatherian divergence. Approximately 53% of the present human miRNA genes have originated within the simian lineage to human. In particular, approximately 28% originated within the hominoid lineage. The early phase of placental mammal radiation comprises approximately 28%, while no more than 15% of human miRNAs have been conserved beyond placental mammals. We also clearly showed a general trend, in which the miRNA expression level decreases as the miRNA becomes younger. Intriguingly, amid this decreasing trend of expression, we found one significant rise in the expression level that corresponded to the initial phase of the hominoid lineage, suggesting that increased functional acquisitions of miRNAs originated at this particular period. PMID:23171859

  15. Accelerated Growth Rate and Increased Drought Stress Resilience of the Model Grass Brachypodium distachyon Colonized by Bacillus subtilis B26

    PubMed Central

    Charron, Jean-Benoit; Vali, Hojatollah; Bertrand, Annick; Jabaji, Suha

    2015-01-01

    Plant growth-promoting bacteria (PGB) induce positive effects in plants, for instance, increased growth and reduced abiotic stresses susceptibility. The mechanisms by which these bacteria impact the host plant are numerous, diverse and often specific. Here, we studied the agronomical, molecular and biochemical effects of the endophytic PGB Bacillus subtilis B26 on the full life cycle of Brachypodium distachyon Bd21, an established model species for functional genomics in cereal crops and temperate grasses. Inoculation of Brachypodium with B. subtilis strain B26 increased root and shoot weights, accelerated growth rate and seed yield as compared to control plants. B. subtilis strain B26 efficiently colonized the plant and was recovered from roots, stems and blades as well as seeds of Brachypodium, indicating that the bacterium is able to migrate, spread systemically inside the plant, establish itself in the aerial plant tissues and organs, and is vertically transmitted to seeds. The presence of B. subtilis strain B26 in the seed led to systemic colonization of the next generation of Brachypodium plants. Inoculated Brachypodium seedlings and mature plants exposed to acute and chronic drought stress minimized the phenotypic effect of drought compared to plants not harbouring the bacterium. Protection from the inhibitory effects of drought by the bacterium was linked to upregulation of the drought-response genes, DREB2B-like, DHN3-like and LEA-14-A-like and modulation of the DNA methylation genes, MET1B-like, CMT3-like and DRM2-like, that regulate the process. Additionally, total soluble sugars and starch contents increased in stressed inoculated plants, a biochemical indication of drought tolerance. In conclusion, we show a single inoculation of Brachypodium with a PGB affected the whole growth cycle of the plant, accelerating its growth rates, shortening its vegetative period, and alleviating drought stress effects. These effects are relevant to grasses and cereal

  16. The Impact of Prematriculation Admission Characteristics on Graduation Rates in an Accelerated Doctor of Pharmacy Program

    PubMed Central

    Morin, Anna K.

    2015-01-01

    Objective. To evaluate the impact of admission characteristics on graduation in an accelerated doctor of pharmacy (PharmD) program. Methods. Selected prematriculation characteristics of students entering the graduation class years of 2009-2012 on the Worcester and Manchester campuses of MCPHS University were analyzed and compared for on-time graduation. Results. Eighty-two percent of evaluated students (699 of 852) graduated on time. Students who were most likely to graduate on-time attended a 4-year school, previously earned a bachelor’s degree, had an overall prematriculation grade point average (GPA) greater than or equal to 3.6, and graduated in the spring just prior to matriculating to the university. Factors that reduced the likelihood of graduating on time were also identified. Work experience had a marginal impact on graduating on time. Conclusion. Although there is no certainty in college admission decisions, prematriculation characteristics can help predict the likelihood for academic success of students in an accelerated PharmD program. PMID:26689686

  17. The effects of accelerated growth rates and estrogen implants in prepubertal Holstein heifers on growth, feed efficiency, and blood parameters.

    PubMed

    Lammers, B P; Heinrichs, A J; Kensinger, R S

    1999-08-01

    Sixty-eight Holstein heifers were used to determine the effects of accelerated growth rates by increased nutrient intake and estrogen implants on feed efficiency, structural growth, and blood parameters in heifers between 19 and 39 wk of age. At the beginning of the treatment period, the heifers were assigned to one of four treatment groups by using a randomized complete block design in a 2 x 2 factorial arrangement. The treatments were standard growth rate (700 g/d), accelerated growth rate (1000 g/d), standard growth rate with an estradiol implant, and accelerated growth rate with an estradiol implant. All heifers received the same diet, but dry matter intake was adjusted weekly to achieve the target rate of gain. Accelerating heifer growth rates from 705 to 1007 g/d improved feed efficiency 5.1%, increased the rate of withers height, heart girth, and hip width growth 12, 27, and 27%, respectively, and body condition scores 0.25 points. Estradiol implants improved feed efficiency 2.4% and decreased the rate of withers height 6% and heart girth growth 3.5%. Increased nutrient intake and average daily gain depressed mean plasma growth hormone and urea nitrogen content 17 and 7%, respectively, while elevating insulin-like growth factor-1 levels by 10%. Estradiol implants increased mean plasma growth hormone content by 29% and insulin-like growth factor-1 levels by 17%, but decreased urea nitrogen content by 11%. Feeding prepubertal heifers for accelerated growth rates increased structural growth with a small increase in body condition, whereas estradiol implants improved feed efficiency and decreased the growth rate of withers height and heart girth without affecting the rate of hip width growth. PMID:10480101

  18. Polar cap plasma patch primary linear instability growth rates compared

    NASA Astrophysics Data System (ADS)

    Burston, Robert; Mitchell, Cathryn; Astin, Ivan

    2016-04-01

    Four primary plasma instability processes have been proposed in the literature to explain the generation of phase scintillation associated with polar cap plasma patches. These are the gradient drift, current convective, and Kelvin-Helmholtz instabilities and a small-scale "turbulence" process. In this paper the range of possible values of the linear growth rates for each of these processes is explored using Dynamics Explorer 2 satellite observations. It is found that the inertial turbulence instability is the dominant process, followed by inertial gradient drift, collisional turbulence, and collisional shortwave current convective instabilities. The other processes, such as Kelvin-Helmholtz, collisional gradient drift, and inertial shortwave current convective instabilities, very rarely (<1% of the time) give rise to a growth rate exceeding 1/60, that is deemed to be significant (in publications) to give rise to GPS scintillation.

  19. Experience-dependent enhancement of pitch-specific responses in the auditory cortex is limited to acceleration rates in normal voice range.

    PubMed

    Krishnan, A; Gandour, J T; Suresh, C H

    2015-09-10

    The aim of this study is to determine how pitch acceleration rates within and outside the normal pitch range may influence latency and amplitude of cortical pitch-specific responses (CPR) as a function of language experience (Chinese, English). Responses were elicited from a set of four pitch stimuli chosen to represent a range of acceleration rates (two each inside and outside the normal voice range) imposed on the high rising Mandarin Tone 2. Pitch-relevant neural activity, as reflected in the latency and amplitude of scalp-recorded CPR components, varied depending on language-experience and pitch acceleration of dynamic, time-varying pitch contours. Peak latencies of CPR components were shorter in the Chinese than the English group across stimuli. Chinese participants showed greater amplitude than English for CPR components at both frontocentral and temporal electrode sites in response to pitch contours with acceleration rates inside the normal voice pitch range as compared to pitch contours with acceleration rates that exceed the normal range. As indexed by CPR amplitude at the temporal sites, a rightward asymmetry was observed for the Chinese group only. Only over the right temporal site was amplitude greater in the Chinese group relative to the English. These findings may suggest that the neural mechanism(s) underlying processing of pitch in the right auditory cortex reflect experience-dependent modulation of sensitivity to acceleration in just those rising pitch contours that fall within the bounds of one's native language. More broadly, enhancement of native pitch stimuli and stronger rightward asymmetry of CPR components in the Chinese group is consistent with the notion that long-term experience shapes adaptive, distributed hierarchical pitch processing in the auditory cortex, and reflects an interaction with higher order, extrasensory processes beyond the sensory memory trace. PMID:26166727

  20. Experience-dependent enhancement of pitch-specific responses in the auditory cortex is limited to acceleration rates in normal voice range

    PubMed Central

    Krishnan, Ananthanarayan; Gandour, Jackson T.; Suresh, Chandan H.

    2015-01-01

    The aim of this study is to determine how pitch acceleration rates within and outside the normal pitch range may influence latency and amplitude of cortical pitch-specific responses (CPR) as a function of language experience (Chinese, English). Responses were elicited from a set of four pitch stimuli chosen to represent a range of acceleration rates (two each inside and outside the normal voice range) imposed on the high rising Mandarin Tone 2. Pitch-relevant neural activity, as reflected in the latency and amplitude of scalp-recorded CPR components, varied depending on language-experience and pitch acceleration of dynamic, time-varying pitch contours. Peak latencies of CPR components were shorter in the Chinese than the English group across stimuli. Chinese participants showed greater amplitude than English for CPR components at both frontocentral and temporal electrode sites in response to pitch contours with acceleration rates inside the normal voice pitch range as compared to pitch contours with acceleration rates that exceed the normal range. As indexed by CPR amplitude at the temporal sites, a rightward asymmetry was observed for the Chinese group only. Only over the right temporal site was amplitude greater in the Chinese group relative to the English. These findings may suggest that the neural mechanism(s) underlying processing of pitch in the right auditory cortex reflect experience-dependent modulation of sensitivity to acceleration in just those rising pitch contours that fall within the bounds of one’s native language. More broadly, enhancement of native pitch stimuli and stronger rightward asymmetry of CPR components in the Chinese group is consistent with the notion that long-term experience shapes adaptive, distributed hierarchical pitch processing in the auditory cortex, and reflects an interaction with higher-order, extrasensory processes beyond the sensory memory trace. PMID:26166727

  1. The degree of heart rate asymmetry is crucial for the validity of the deceleration and acceleration capacity indices of heart rate: A model-based study.

    PubMed

    Pan, Qing; Zhou, Gongzhan; Wang, Ruofan; Yu, Yihua; Li, Feng; Fang, Luping; Yan, Jing; Ning, Gangmin

    2016-09-01

    The deceleration capacity (DC) and acceleration capacity (AC) of heart rate are a pair of indices used for evaluating the autonomic nervous system (ANS). We assessed the role of heart rate asymmetry (HRA) in defining the relative performance of DC and AC using a mathematical model, which is able to generate a realistic RR interval (RRI) time series with controlled ANS states. The simulation produced a set of RRI series with random sympathetic and vagal activities. The multi-scale DCs and ACs were computed from the RRI series, and the correlation of DC and AC with the ANS functions was analyzed to evaluate the performance of the indices. In the model, the HRA level was modified by changing the inspiration/expiration (I/E) ratio to examine the influence of HRA on the performances of DC and AC. The results show that on the conventional scales (T=1, s=2), an HRA level above 50% results in a stronger association of DC with the ANS, compared with AC. On higher scales (T=4, s=6), there was no HRA and DC showed a similar performance to AC for all I/E ratios. The data suggest that the HRA level determines which of DC or AC is the optimal index for expressing ANS functions. Future clinical applications of DC and AC should be accompanied by an HRA analysis to provide a better index for assessing ANS. PMID:27392228

  2. Effect of initial acceleration on the development of the flow field of an airfoil pitching at constant rate

    NASA Technical Reports Server (NTRS)

    Koochesfahani, M. M.; Smiljanovski, V.; Brown, T. A.

    1992-01-01

    We present results from a series of experiments where an airfoil is pitched at constant rate from 0 to 60 degrees angle of attack. It is well documented that the dynamic stall behavior of such an airfoil strongly depends on the nondimensional pitch rate K = dot-alpha C/(2U(sub infinity)), where C is the chord, dot-alpha the constant pitch rate, and U(sub infinity) the free stream speed. In reality, the actual motion of the airfoil deviates from the ideal ramp due to the finite acceleration and deceleration periods imposed by the damping of drive system and response characteristics of the airfoil. It is possible that the pitch rate alone may not suffice in describing the flow and that the details of the motion trajectory before achieving a desired constant pitch rate may also affect the processes involved in the dynamic stall phenomenon. The effects of acceleration and deceleration periods are investigated by systematically varing the acceleration magnitude and its duration through the initial acceleration phase to constant pitch rate. The magnitude and duration of deceleration needed to bring the airfoil motion to rest is similarly controlled.

  3. Isolation of Hox cluster genes from insects reveals an accelerated sequence evolution rate.

    PubMed

    Hadrys, Heike; Simon, Sabrina; Kaune, Barbara; Schmitt, Oliver; Schöner, Anja; Jakob, Wolfgang; Schierwater, Bernd

    2012-01-01

    Among gene families it is the Hox genes and among metazoan animals it is the insects (Hexapoda) that have attracted particular attention for studying the evolution of development. Surprisingly though, no Hox genes have been isolated from 26 out of 35 insect orders yet, and the existing sequences derive mainly from only two orders (61% from Hymenoptera and 22% from Diptera). We have designed insect specific primers and isolated 37 new partial homeobox sequences of Hox cluster genes (lab, pb, Hox3, ftz, Antp, Scr, abd-a, Abd-B, Dfd, and Ubx) from six insect orders, which are crucial to insect phylogenetics. These new gene sequences provide a first step towards comparative Hox gene studies in insects. Furthermore, comparative distance analyses of homeobox sequences reveal a correlation between gene divergence rate and species radiation success with insects showing the highest rate of homeobox sequence evolution. PMID:22685537

  4. Rate-related accelerating (autodecremental) atrial pacing for reversion of paroxysmal supraventricular tachycardia.

    PubMed

    Nathan, A; Hellestrand, K; Ward, D; Spurrell, R; Camm, J

    1982-01-01

    Twenty consecutive patients with paroxysmal intra A-V nodal or atrio-ventricular tachycardia had a new tachycardia reversion pacing modality evaluated during routine electrophysiological study. The pacing was controlled by a micropressor interfaced with a stimulator connected to a right atrial pacing electrode. On detection of tachycardia the first pacing cycle interval is equal to the tachycardia cycle length minus a decrement value D. Each subsequent pacing cycle is further reduced by the same value of D, thus accelerating the pacing burst until a plateau of 100 beats/min faster than tachycardia (with an absolute lower limit of 275 beats/min) is reached. Seven different values of D (2, 4, 8, 16, 24, 34, 50 msec) were assessed in combination with three different durations of pacing P (500, 5000 msec). With P:500, only 2/20 tachycardias were terminated, but with P:1000, 16/20 were terminated. With P:5000 all were terminated and the combination successful in all patients was P:5000 and D:16. No unwanted arrhythmias were induced. In contrast, competitive constant rate overdrive atrial pacing accomplished tachycardia termination in all cases, but in four instances resulted in atrial flutter or fibrillation. Autodecremental pacing, which tends to avoid stimulation in the vulnerable period, allowed safe and successful termination of all tachycardias evaluated in this study. PMID:7069321

  5. Rotational IMRT delivery using a digital linear accelerator in very high dose rate 'burst mode'.

    PubMed

    Salter, Bill J; Sarkar, Vikren; Wang, Brian; Shukla, Himanshu; Szegedi, Martin; Rassiah-Szegedi, Prema

    2011-04-01

    Recently, there has been a resurgence of interest in arc-based IMRT, through the use of 'conventional' multileaf collimator (MLC) systems that can treat large tumor volumes in a single, or very few pass(es) of the gantry. Here we present a novel 'burst mode' modulated arc delivery approach, wherein 2000 monitor units per minute (MU min(-1)) high dose rate bursts of dose are facilitated by a flattening-filter-free treatment beam on a Siemens Artiste (Oncology Care Systems, Siemens Medical Solutions, Concord, CA, USA) digital linear accelerator in a non-clinical configuration. Burst mode delivery differs from continuous mode delivery, used by Elekta's VMAT (Elekta Ltd, Crawley, UK) and Varian's RapidArc (Varian Medical Systems, Palo Alto, CA, USA) implementations, in that dose is not delivered while MLC leaves are moving. Instead, dose is delivered in bursts over very short arc angles and only after an MLC segment shape has been completely formed and verified by the controller. The new system was confirmed to be capable of delivering a wide array of clinically relevant treatment plans, without machine fault or other delivery anomalies. Dosimetric accuracy of the modulated arc platform, as well as the Prowess (Prowess Inc., Concord, CA, USA) prototype treatment planning version utilized here, was quantified and confirmed, and delivery times were measured as significantly brief, even with large hypofractionated doses. The burst mode modulated arc approach evaluated here appears to represent a capable, accurate and efficient delivery approach. PMID:21364260

  6. Thermal runaway features of large format prismatic lithium ion battery using extended volume accelerating rate calorimetry

    NASA Astrophysics Data System (ADS)

    Feng, Xuning; Fang, Mou; He, Xiangming; Ouyang, Minggao; Lu, Languang; Wang, Hao; Zhang, Mingxuan

    2014-06-01

    In this paper, the thermal runaway features of a 25 Ah large format prismatic lithium ion battery with Li(NixCoyMnz)O2 (NCM) cathode are evaluated using the extended volume-accelerating rate calorimetry (EV-ARC). 4 thermocouples are set at different positions of the battery. The temperature inside the battery is 870 °C or so, much higher than that outside the battery. The temperature difference is calculated from the recorded data. The temperature difference within the battery stays lower than 1 °C for 97% of the test period, while it rises to its highest, approximately 520 °C, when thermal runaway happens. The voltage of the battery is also measured during the test. It takes 15-40 s from the sharp drop of voltage to the instantaneous rise of temperature. Such a time interval is beneficial for early warning of the thermal runaway. Using a pulse charge/discharge profile, the internal resistance is derived from the quotient of the pulse voltage and the current during the ARC test. The internal resistance of the battery increases slowly from 20 mΩ to 60 mΩ before thermal runaway, while it rises to 370 mΩ when thermal runaway happens indicating the loss of the integrity of the separator or the battery swell.

  7. The neurotransmitters serotonin and glutamate accelerate the heart rate of the mosquito Anopheles gambiae.

    PubMed

    Hillyer, Julián F; Estévez-Lao, Tania Y; Mirzai, Homa E

    2015-10-01

    Serotonin and glutamate are neurotransmitters that in insects are involved in diverse physiological processes. Both serotonin and glutamate have been shown to modulate the physiology of the dorsal vessel of some insects, yet until the present study, their activity in mosquitoes remained unknown. To test whether serotonin or glutamate regulate dorsal vessel physiology in the African malaria mosquito, Anopheles gambiae, live mosquitoes were restrained, and a video of the contracting heart (the abdominal portion of the dorsal vessel) was acquired. These adult female mosquitoes were then injected with various amounts of serotonin, glutamate, or a control vehicle solution, and additional videos were acquired at 2 and 10 min post-treatment. Comparison of the videos taken before and after treatment revealed that serotonin accelerates the frequency of heart contractions, with the cardioacceleration being significantly more pronounced when the wave-like contractions of cardiac muscle propagate in the anterograde direction (toward the head). Comparison of the videos taken before and after treatment with glutamate revealed that this molecule is also cardioacceleratory. However, unlike serotonin, the activity of glutamate does not depend on whether the contractions propagate in the anterograde or the retrograde (toward the posterior of the abdomen) directions. Serotonin or glutamate induces a minor change or no change in the percentage of contractions and the percentage of the time that the heart contracts in the anterograde or the retrograde directions. In summary, this study shows that the neurotransmitters serotonin and glutamate increase the heart contraction rate of mosquitoes. PMID:26099947

  8. Decadal trends reveal recent acceleration in the rate of recovery from acidification in the northeastern U.S.

    PubMed

    Strock, Kristin E; Nelson, Sarah J; Kahl, Jeffrey S; Saros, Jasmine E; McDowell, William H

    2014-05-01

    Previous reports suggest variable trends in recovery from acidification in northeastern U.S. surface waters in response to the Clean Air Act Amendments. Here we analyze recent trends in emissions, wet deposition, and lake chemistry using long-term data from a variety of lakes in the Adirondack Mountains and New England. Sulfate concentration in wet deposition declined by more than 40% in the 2000s and sulfate concentration in lakes declined at a greater rate from 2002 to 2010 than during the 1980s or 1990s (-3.27 μeq L(-1)year(-1) as compared to -1.26 μeq L(-1)year(-1)). During the 2000s, nitrate concentration in wet deposition declined by more than 50% and nitrate concentration in lakes, which had no linear trend prior to 2000, declined at a rate of -0.05 μeq L(-1)year(-1). Base cation concentrations, which decreased during the 1990s (-1.5 μeq L(-1) year(-1)), have stabilized in New England lakes. Although total aluminum concentrations increased since 1999 (2.57 μg L(-1) year(-1)), there was a shift to nontoxic, organic aluminum. Despite this recent acceleration in recovery in multiple variables, both ANC and pH continue to have variable trends. This may be due in part to variable trajectories in the concentrations of base cations and dissolved organic carbon among our study lakes. PMID:24669928

  9. Mimosoid legume plastome evolution: IR expansion, tandem repeat expansions, and accelerated rate of evolution in clpP

    PubMed Central

    Dugas, Diana V.; Hernandez, David; Koenen, Erik J.M.; Schwarz, Erika; Straub, Shannon; Hughes, Colin E.; Jansen, Robert K.; Nageswara-Rao, Madhugiri; Staats, Martijn; Trujillo, Joshua T.; Hajrah, Nahid H.; Alharbi, Njud S.; Al-Malki, Abdulrahman L.; Sabir, Jamal S. M.; Bailey, C. Donovan

    2015-01-01

    The Leguminosae has emerged as a model for studying angiosperm plastome evolution because of its striking diversity of structural rearrangements and sequence variation. However, most of what is known about legume plastomes comes from few genera representing a subset of lineages in subfamily Papilionoideae. We investigate plastome evolution in subfamily Mimosoideae based on two newly sequenced plastomes (Inga and Leucaena) and two recently published plastomes (Acacia and Prosopis), and discuss the results in the context of other legume and rosid plastid genomes. Mimosoid plastomes have a typical angiosperm gene content and general organization as well as a generally slow rate of protein coding gene evolution, but they are the largest known among legumes. The increased length results from tandem repeat expansions and an unusual 13 kb IR-SSC boundary shift in Acacia and Inga. Mimosoid plastomes harbor additional interesting features, including loss of clpP intron1 in Inga, accelerated rates of evolution in clpP for Acacia and Inga, and dN/dS ratios consistent with neutral and positive selection for several genes. These new plastomes and results provide important resources for legume comparative genomics, plant breeding, and plastid genetic engineering, while shedding further light on the complexity of plastome evolution in legumes and angiosperms. PMID:26592928

  10. Mimosoid legume plastome evolution: IR expansion, tandem repeat expansions, and accelerated rate of evolution in clpP.

    PubMed

    Dugas, Diana V; Hernandez, David; Koenen, Erik J M; Schwarz, Erika; Straub, Shannon; Hughes, Colin E; Jansen, Robert K; Nageswara-Rao, Madhugiri; Staats, Martijn; Trujillo, Joshua T; Hajrah, Nahid H; Alharbi, Njud S; Al-Malki, Abdulrahman L; Sabir, Jamal S M; Bailey, C Donovan

    2015-01-01

    The Leguminosae has emerged as a model for studying angiosperm plastome evolution because of its striking diversity of structural rearrangements and sequence variation. However, most of what is known about legume plastomes comes from few genera representing a subset of lineages in subfamily Papilionoideae. We investigate plastome evolution in subfamily Mimosoideae based on two newly sequenced plastomes (Inga and Leucaena) and two recently published plastomes (Acacia and Prosopis), and discuss the results in the context of other legume and rosid plastid genomes. Mimosoid plastomes have a typical angiosperm gene content and general organization as well as a generally slow rate of protein coding gene evolution, but they are the largest known among legumes. The increased length results from tandem repeat expansions and an unusual 13 kb IR-SSC boundary shift in Acacia and Inga. Mimosoid plastomes harbor additional interesting features, including loss of clpP intron1 in Inga, accelerated rates of evolution in clpP for Acacia and Inga, and dN/dS ratios consistent with neutral and positive selection for several genes. These new plastomes and results provide important resources for legume comparative genomics, plant breeding, and plastid genetic engineering, while shedding further light on the complexity of plastome evolution in legumes and angiosperms. PMID:26592928

  11. Comparative Oxidative Stability of Fatty Acid Alkyl Esters by Accelerated Methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several fatty acid alkyl esters were subjected to accelerated methods of oxidation, including EN 14112 (Rancimat method) and pressurized differential scanning calorimetry (PDSC). Structural trends elucidated from both methods that improved oxidative stability included decreasing the number of doubl...

  12. MRI-based brain atrophy rates in ADNI phase 2: acceleration and enrichment considerations for clinical trials.

    PubMed

    Hua, Xue; Ching, Christopher R K; Mezher, Adam; Gutman, Boris A; Hibar, Derrek P; Bhatt, Priya; Leow, Alex D; Jack, Clifford R; Bernstein, Matt A; Weiner, Michael W; Thompson, Paul M

    2016-01-01

    The goal of this work was to assess statistical power to detect treatment effects in Alzheimer's disease (AD) clinical trials using magnetic resonance imaging (MRI)-derived brain biomarkers. We used unbiased tensor-based morphometry (TBM) to analyze n = 5,738 scans, from Alzheimer's Disease Neuroimaging Initiative 2 participants scanned with both accelerated and nonaccelerated T1-weighted MRI at 3T. The study cohort included 198 healthy controls, 111 participants with significant memory complaint, 182 with early mild cognitive impairment (EMCI) and 177 late mild cognitive impairment (LMCI), and 155 AD patients, scanned at screening and 3, 6, 12, and 24 months. The statistical power to track brain change in TBM-based imaging biomarkers depends on the interscan interval, disease stage, and methods used to extract numerical summaries. To achieve reasonable sample size estimates for potential clinical trials, the minimal scan interval was 6 months for LMCI and AD and 12 months for EMCI. TBM-based imaging biomarkers were not sensitive to MRI scan acceleration, which gave results comparable with nonaccelerated sequences. ApoE status and baseline amyloid-beta positron emission tomography data improved statistical power. Among healthy, EMCI, and LMCI participants, sample size requirements were significantly lower in the amyloid+/ApoE4+ group than for the amyloid-/ApoE4- group. ApoE4 strongly predicted atrophy rates across brain regions most affected by AD, but the remaining 9 of the top 10 AD risk genes offered no added predictive value in this cohort. PMID:26545631

  13. Effects of Sled Towing on Peak Force, the Rate of Force Development and Sprint Performance During the Acceleration Phase

    PubMed Central

    Martínez-Valencia, María Asunción; Romero-Arenas, Salvador; Elvira, José L.L.; González-Ravé, José María; Navarro-Valdivielso, Fernando; Alcaraz, Pedro E.

    2015-01-01

    Resisted sprint training is believed to increase strength specific to sprinting. Therefore, the knowledge of force output in these tasks is essential. The aim of this study was to analyze the effect of sled towing (10%, 15% and 20% of body mass (Bm)) on sprint performance and force production during the acceleration phase. Twenty-three young experienced sprinters (17 men and 6 women; men = 17.9 ± 3.3 years, 1.79 ± 0.06 m and 69.4 ± 6.1 kg; women = 17.2 ± 1.7 years, 1.65 ± 0.04 m and 56.6 ± 2.3 kg) performed four 30 m sprints from a crouch start. Sprint times in 20 and 30 m sprint, peak force (Fpeak), a peak rate of force development (RFDpeak) and time to RFD (TRFD) in first step were recorded. Repeated-measures ANOVA showed significant increases (p ≤ 0.001) in sprint times (20 and 30 m sprint) for each resisted condition as compared to the unloaded condition. The RFDpeak increased significantly when a load increased (3129.4 ± 894.6 N·s−1, p ≤ 0.05 and 3892.4 ± 1377.9 N·s−1, p ≤ 0.01). Otherwise, no significant increases were found in Fpeak and TRFD. The RFD determines the force that can be generated in the early phase of muscle contraction, and it has been considered a factor that influences performance of force-velocity tasks. The use of a load up to 20% Bm might provide a training stimulus in young sprinters to improve the RFDpeak during the sprint start, and thus, early acceleration. PMID:26240657

  14. Effects of Sled Towing on Peak Force, the Rate of Force Development and Sprint Performance During the Acceleration Phase.

    PubMed

    Martínez-Valencia, María Asunción; Romero-Arenas, Salvador; Elvira, José L L; González-Ravé, José María; Navarro-Valdivielso, Fernando; Alcaraz, Pedro E

    2015-06-27

    Resisted sprint training is believed to increase strength specific to sprinting. Therefore, the knowledge of force output in these tasks is essential. The aim of this study was to analyze the effect of sled towing (10%, 15% and 20% of body mass (Bm)) on sprint performance and force production during the acceleration phase. Twenty-three young experienced sprinters (17 men and 6 women; men = 17.9 ± 3.3 years, 1.79 ± 0.06 m and 69.4 ± 6.1 kg; women = 17.2 ± 1.7 years, 1.65 ± 0.04 m and 56.6 ± 2.3 kg) performed four 30 m sprints from a crouch start. Sprint times in 20 and 30 m sprint, peak force (Fpeak), a peak rate of force development (RFDpeak) and time to RFD (TRFD) in first step were recorded. Repeated-measures ANOVA showed significant increases (p ≤ 0.001) in sprint times (20 and 30 m sprint) for each resisted condition as compared to the unloaded condition. The RFDpeak increased significantly when a load increased (3129.4 ± 894.6 N·s-1, p ≤ 0.05 and 3892.4 ± 1377.9 N·s-1, p ≤ 0.01). Otherwise, no significant increases were found in Fpeak and TRFD. The RFD determines the force that can be generated in the early phase of muscle contraction, and it has been considered a factor that influences performance of force-velocity tasks. The use of a load up to 20% Bm might provide a training stimulus in young sprinters to improve the RFDpeak during the sprint start, and thus, early acceleration. PMID:26240657

  15. Language-Dependent Pitch Encoding Advantage in the Brainstem Is Not Limited to Acceleration Rates that Occur in Natural Speech

    ERIC Educational Resources Information Center

    Krishnan, Ananthanarayan; Gandour, Jackson T.; Smalt, Christopher J.; Bidelman, Gavin M.

    2010-01-01

    Experience-dependent enhancement of neural encoding of pitch in the auditory brainstem has been observed for only specific portions of native pitch contours exhibiting high rates of pitch acceleration, irrespective of speech or nonspeech contexts. This experiment allows us to determine whether this language-dependent advantage transfers to…

  16. An investigation of how radiation may cause accelerated rates of tropical cyclogenesis and diurnal cycles of convective activity

    NASA Astrophysics Data System (ADS)

    Nicholls, M. E.

    2015-03-01

    Recent cloud-resolving numerical modeling results suggest that radiative forcing causes accelerated rates of tropical cyclogenesis and early intensification. Furthermore, observational studies of tropical cyclones have found that oscillations of the cloud canopy areal extent often occur that are clearly related to the solar diurnal cycle. A theory is put forward to explain these findings. The primary mechanism that seems responsible can be considered a refinement of the mechanism proposed by Gray and Jacobson (1977) to explain diurnal variations of oceanic tropical deep cumulus convection. It is hypothesized that differential radiative cooling or heating between a relatively cloud-free environment and a developing tropical disturbance generates circulations that can have very significant influences on convective activity in the core of the system. It is further suggested that there are benefits to understanding this mechanism by viewing it in terms of the lateral propagation of thermally driven gravity wave circulations, also known as buoyancy bores. Numerical model experiments indicate that mean environmental radiative cooling outside the cloud system is playing an important role in causing a significant horizontal differential radiative forcing and accelerating the rate of tropical cyclogenesis. As an expansive stratiform cloud layer forms aloft within a developing system the mean low level radiative cooling is reduced while at mid levels small warming occurs. During the daytime there is not a very large differential radiative forcing between the environment and the cloud system, but at nighttime when there is strong radiative clear sky cooling of the environment it becomes significant. Thermally driven circulations develop, characterized by relatively weak subsidence in the environment but much stronger upward motion in the cloud system. This upward motion leads to a cooling tendency and increased relative humidity. The increased relative humidity at night

  17. An investigation of how radiation may cause accelerated rates of tropical cyclogenesis and diurnal cycles of convective activity

    NASA Astrophysics Data System (ADS)

    Nicholls, M. E.

    2015-08-01

    Recent cloud-resolving numerical modeling results suggest that radiative forcing causes accelerated rates of tropical cyclogenesis and early intensification. Furthermore, observational studies of tropical cyclones have found that oscillations of the cloud canopy areal extent often occur that are clearly related to the solar diurnal cycle. A theory is put forward to explain these findings. The primary mechanism that seems responsible can be considered a refinement of the mechanism proposed by Gray and Jacobson (1977) to explain diurnal variations of oceanic tropical deep cumulus convection. It is hypothesized that differential radiative cooling or heating between a relatively cloud-free environment and a developing tropical disturbance generates circulations that can have very significant influences on convective activity in the core of the system. It is further suggested that there are benefits to understanding this mechanism by viewing it in terms of the lateral propagation of thermally driven gravity wave circulations, also known as buoyancy bores. Numerical model experiments indicate that mean environmental radiative cooling outside the cloud system is playing an important role in causing a significant horizontal differential radiative forcing and accelerating the rate of tropical cyclogenesis. As an expansive stratiform cloud layer forms aloft within a developing system the mean low-level radiative cooling is reduced, while at mid levels small warming occurs. During the daytime there is not a very large differential radiative forcing between the environment and the cloud system, but at nighttime when there is strong radiative clear-sky cooling of the environment it becomes significant. Thermally driven circulations develop, characterized by relatively weak subsidence in the environment but much stronger upward motion in the cloud system. This upward motion leads to a cooling tendency and increased relative humidity. The increased relative humidity at night

  18. Cycle-Powered Short Radius (1.9 m) Centrifuge: Effect of Exercise Versus Passive Acceleration on Heart Rate in Humans

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.; Gundo, D. P.; Watenpaugh, D. E.; Mulenburg, G. M.; Mckenzie, M. A.; Looft-Wilson, R.; Hargens, A. R.

    1997-01-01

    In addition to extensive use of lower extremity physical exercise training as a countermeasure for the work capacity component of spaceflight deconditioning, some form of additional head-to-foot (+Gz) gravitational (orthostatic) stress may be required to further attenuate or prevent the signs and symptoms (nausea, vertigo, instability, fatigue) of the general reentry syndrome (GRS) that can reduce astronaut performance during landing. Orthostatic (head-to-foot) stress can be induced by standing, by lower body negative pressure, and by +Gz acceleration. One important question is whether acceleration training alone or with concurrent leg exercise would provide sufficient additive stimulation to attenuate the GRS. Use of a new human-powered centrifuge may be the answer. Thus, the purpose for this study was to compare heart rate (HR), i.e., a stress response during human-powered acceleration, in four men (35-62 yr) and two women (30-31 yr) during exercise acceleration versus passive acceleration (by an off-board operator) at 100% (maximal acceleration = A(max)), and at 25%, 50%, and 75% of A(max). Mean (+/-SE) A(max) was 43.7 +/- 1.3 rpm (+3.9 +/- 0.2Gz). Mean HR at exercise A(max) was 189 +/- 13 b/min (50-70 sec run time), and 142 +/- 22 b/min at passive A(max) (40-70 sec run time). Regression of mean HR on the various +Gz levels indicated explained variance (correlations squared) of r(exp 2) = 0.88 (exercise) and r(exp 2) = 0.96 (passive): exercise HR of 107 +/- 4 (25%) to 189 +/- 13 (100%) b/min were 43-50 b/min higher (p less than 0.05) than comparable passive HR of 64 +/- 2 to 142 +/- 22 b/min. Thus, exercise adds significant physiological stress during +Gz acceleration. Inflight use of this combined exercise and acceleration countermeasure may maintain work capacity as well as normalize acceleration and orthostatic tolerances which could attenuate or perhaps eliminate the GRS.

  19. The acceleration rate of cosmic rays at cosmic ray modified shocks

    NASA Astrophysics Data System (ADS)

    Saito, Tatsuhiko; Hoshino, Masahiro; Amano, Takanobu

    It is a still controversial matter whether the production efficiency of cosmic rays (CRs) is relatively efficient or inefficient (e.g. Helder et al. 2009; Hughes et al. 2000; Fukui 2013). In upstream region of SNR shocks (the interstellar medium), the energy density of CRs is comparable to a substantial fraction of that of the thermal plasma (e.g. Ferriere 2001). In such a situation, CRs can possibly exert a back-reaction to the shocks and modify the global shock structure. These shocks are called cosmic ray modified shocks (CRMSs). In CRMSs, as a result of the nonlinear feedback, there are almost always up to three steady-state solutions for given upstream parameters, which are characterized by CR production efficiencies (efficient, intermediate and inefficient branch). We evaluate qualitatively the efficiency of the CR production in SNR shocks by considering the stability of CRMS, under the effects of i) magnetic fields and ii) injection, which play significant roles in efficiency of acceleration. By adopting two-fluid model (Drury & Voelk, 1981), we investigate the stability of CRMSs by means of time-dependent numerical simulations. As a result, we show explicitly the bi-stable feature of these multiple solutions, i.e., the efficient and inefficient branches are stable and the intermediate branch is unstable, and the intermediate branch transit to the inefficient one. This feature is independent of the effects of i) shock angles and ii) injection. Furthermore, we investigate the evolution from a hydrodynamic shock to CRMS in a self-consistent manner. From the results, we suggest qualitatively that the CR production efficiency at SNR shocks may be the least efficient.

  20. Dual-mass vibratory rate gyroscope with suppressed translational acceleration response and quadrature-error correction capability

    NASA Technical Reports Server (NTRS)

    Clark, William A. (Inventor); Juneau, Thor N. (Inventor); Lemkin, Mark A. (Inventor); Roessig, Allen W. (Inventor)

    2001-01-01

    A microfabricated vibratory rate gyroscope to measure rotation includes two proof-masses mounted in a suspension system anchored to a substrate. The suspension has two principal modes of compliance, one of which is driven into oscillation. The driven oscillation combined with rotation of the substrate about an axis perpendicular to the substrate results in Coriolis acceleration along the other mode of compliance, the sense-mode. The sense-mode is designed to respond to Coriolis accelerationwhile suppressing the response to translational acceleration. This is accomplished using one or more rigid levers connecting the two proof-masses. The lever allows the proof-masses to move in opposite directions in response to Coriolis acceleration. The invention includes a means for canceling errors, termed quadrature error, due to imperfections in implementation of the sensor. Quadrature-error cancellation utilizes electrostatic forces to cancel out undesired sense-axis motion in phase with drive-mode position.

  1. Determination of the cosmological rate of change of G and the tidal accelerations of earth and moon from ancient and modern astronomical data

    NASA Technical Reports Server (NTRS)

    Muller, P. M.

    1976-01-01

    The theory and numerical analysis of ancient astronomical observations (1374 to 1715) are combined with modern data in a simultaneous solution for: the tidal acceleration of the lunar longitude; the observed apparent acceleration of the earth's rotation; the true nontidal geophysical part of this acceleration; and the rate of change in the gravitational constant. Provided are three independent determinations of a rate of change of G consistent with the Hubble Constant and a near zero nontidal rotational acceleration of the earth. The tidal accelerations are shown to have remained constant during the historical period within uncertainties. Ancient and modern solar system data, and extragalactic observations provided a completely consistent astronomical and cosmological scheme.

  2. The Effect of Maternal Relaxation Training on Reactivity of Non-Stress Test, Basal Fetal Heart Rate, and Number of Fetal Heart Accelerations: A Randomized Controlled Trial

    PubMed Central

    Akbarzade, Marzieh; Rafiee, Bahare; Asadi, Nasrin; Zare, Najaf

    2015-01-01

    Background: Relaxation-training, as an anxiety-reducer intervention, plays an important role in fetal health. The present study aimed to analyze the effect of maternal relaxation on stress test (NST), basal fetal heart rate, and number of fetal heart accelerations. Methods: In this randomized controlled trial, 84 pregnant women were randomly divided into two groups of teaching relaxation and control groups in 2012. In the intervention group, 60-90 minute classes were held every week lasting for 4 weeks. Besides, home practice charts were given to the mothers and researchers controlled the home practices by phone calls every week. The control group received routine prenatal care. In the 4th week, NST was performed in the intervention group 30 minutes before and after the 4th session. In the control group, NST was done in the 4th week. The quantitative variables in the two groups were compared through ANOVA and Chi-square test. Results: The results of paired t-test showed that relaxation could improve the NST results (P=0.01). Mean and standard deviation of basal fetal heart rate was 138.95±8.18 before the intervention and 133.07±6.9 after the intervention. Paired t-test also showed that relaxation reduced the basal fetal heart rate (P=0.001). Mean and standard deviation of the number of fetal heart accelerations was 1.5±0.8 before the intervention and 2.2±0.9 after it. The results of paired t-test also showed that relaxation increased the number of fetal heart accelerations (P=0.001). Conclusions: Relaxation could improve the NST results, reduce the basal fetal heart rate, and increase the number of fetal heart accelerations. Therefore, relaxation is recommended during pregnancy. Trial Registration Number: IRCT2012072810418N1 PMID:25553334

  3. Low-to-moderate nitrogen and phosphorus concentrations accelerate microbially driven litter breakdown rates.

    PubMed

    Kominoski, John S; Rosemond, Amy D; Benstead, Jonathan P; Gulis, Vladislav; Maerz, John C; Manning, David W P

    2015-04-01

    Particulate organic matter (POM) processing is an important driver of aquatic ecosystem productivity that is sensitive to nutrient enrichment and.drives ecosystem carbon (C) loss. Although studies of single concentrations of nitrogen (N) or phosphorus (P) have shown effects at relatively low concentrations, responses of litter breakdown rates along gradients of low-to-moderate N and P concentrations are needed to establish likely interdependent effects of dual N and P enrichment on baseline activity in stream ecosystems. We established 25 combinations of dissolved inorganic N (DIN; 55-545 µg/L) and soluble reactive P (SRP; 4-86 µg/L) concentrations with corresponding N:P molar ratios of 2-127 in experimental stream channels. We excluded macroinvertebrates, focusing on microbially driven breakdown of maple (Acer rubrum L.) and rhododendron (Rhododendron maximum L.) leaf litter. Breakdown rates, k, per day (d-1) and per degree-day (dd-l), increased by up to 6X for maple and 12× for rhododendron over our N and P enrichment gradient compared to rates at low ambient N and P concentrations. The best models of k (d- and dd-1) included litter species identity and N and P concentrations; there was evidence for both additive and interactive effects of N and P. Models explaining variation in k dd-1 were supported by N and P for both maple and rhododendron (R =0.67 and 0.33, respectively). Residuals in the relationship between k dd-1 and N concentration were largely explained by P, but residuals for k dd-1 and P. concentration were less adequately explained by N. Breakdown rates were more closely related to nutrient concentrations than variables associated with measurements of two mechanistic parameters associated with C loss (fungal biomass and microbial respiration rate). We also determined the effects of nutrient addition on litter C: nutrient stoichiometry and found reductions in litter C:N and C:P along our experimental nutrient gradient. Our results indicate that

  4. Offenders, Judges, and Officers Rate the Relative Severity of Alternative Sanctions Compared to Prison

    ERIC Educational Resources Information Center

    Moore, Nathan T.; May, David C.; Wood, Peter B.

    2008-01-01

    Recent work suggests that offenders rate several alternatives as more severe than imprisonment. We build on this literature by comparing punishment exchange rates generated by criminal court judges with rates generated by offenders and their supervising officers. Findings reveal that none of the three groups rates prison as the most severe…

  5. Technology evaluation of man-rated acceleration test equipment for vestibular research

    NASA Technical Reports Server (NTRS)

    Taback, I.; Kenimer, R. L.; Butterfield, A. J.

    1983-01-01

    The considerations for eliminating acceleration noise cues in horizontal, linear, cyclic-motion sleds intended for both ground and shuttle-flight applications are addressed. the principal concerns are the acceleration transients associated with change in direction-of-motion for the carriage. The study presents a design limit for acceleration cues or transients based upon published measurements for thresholds of human perception to linear cyclic motion. The sources and levels for motion transients are presented based upon measurements obtained from existing sled systems. The approaches to a noise-free system recommends the use of air bearings for the carriage support and moving-coil linear induction motors operating at low frequency as the drive system. Metal belts running on air bearing pulleys provide an alternate approach to the driving system. The appendix presents a discussion of alternate testing techniques intended to provide preliminary type data by means of pendulums, linear motion devices and commercial air bearing tables.

  6. Comparative study on cost evaluation and network visualization of particle accelerator components for heavy ion inertial fusion

    NASA Astrophysics Data System (ADS)

    Inoue, A.; Takahashi, K.; Sasaki, T.; Kikuchi, T.; Harada, Nob; Barnard, J. J.

    2016-05-01

    By visualizing accelerator system components in heavy ion inertial fusion, the connection between the components becomes clear. We clarify an influential component on the entire cost by the relation of node connections due to the visualization result. Since a low cost component affects a high cost component, not only the cost estimation but also the relation between the components is considerable and important issue. A cost estimation result changing with an induction core cost indicates no influences in the rate of details.

  7. Setting accelerated dissolution test for PLGA microspheres containing peptide, investigation of critical parameters affecting drug release rate and mechanism.

    PubMed

    Tomic, I; Vidis-Millward, A; Mueller-Zsigmondy, M; Cardot, J-M

    2016-05-30

    The objective of this study was development of accelerated in vitro release method for peptide loaded PLGA microspheres using flow-through apparatus and assessment of the effect of dissolution parameters (pH, temperature, medium composition) on drug release rate and mechanism. Accelerated release conditions were set as pH 2 and 45°C, in phosphate buffer saline (PBS) 0.02M. When the pH was changed from 2 to 4, diffusion controlled phases (burst and lag) were not affected, while release rate during erosion phase decreased two-fold due to slower ester bonds hydrolyses. Decreasing temperature from 45°C to 40°C, release rate showed three-fold deceleration without significant change in release mechanism. Effect of medium composition on drug release was tested in PBS 0.01M (200 mOsm/kg) and PBS 0.01M with glucose (380 mOsm/kg). Buffer concentration significantly affected drug release rate and mechanism due to the change in osmotic pressure, while ionic strength did not have any effect on peptide release. Furthermore, dialysis sac and sample-and-separate techniques were used, in order to evaluate significance of dissolution technique choice on the release process. After fitting obtained data to different mathematical models, flow-through method was confirmed as the most appropriate for accelerated in vitro dissolution testing for a given formulation. PMID:27025293

  8. In Vivo Human Left-to-Right Ventricular Differences in Rate Adaptation Transiently Increase Pro-Arrhythmic Risk following Rate Acceleration

    PubMed Central

    Bueno-Orovio, Alfonso; Hanson, Ben M.; Gill, Jaswinder S.; Taggart, Peter; Rodriguez, Blanca

    2012-01-01

    Left-to-right ventricular (LV/RV) differences in repolarization have been implicated in lethal arrhythmias in animal models. Our goal is to quantify LV/RV differences in action potential duration (APD) and APD rate adaptation and their contribution to arrhythmogenic substrates in the in vivo human heart using combined in vivo and in silico studies. Electrograms were acquired from 10 LV and 10 RV endocardial sites in 15 patients with normal ventricles. APD and APD adaptation were measured during an increase in heart rate. Analysis of in vivo electrograms revealed longer APD in LV than RV (207.8±21.5 vs 196.7±20.1 ms; P<0.05), and slower APD adaptation in LV than RV (time constant τs = 47.0±14.3 vs 35.6±6.5 s; P<0.05). Following rate acceleration, LV/RV APD dispersion experienced an increase of up to 91% in 12 patients, showing a strong correlation (r2 = 0.90) with both initial dispersion and LV/RV difference in slow adaptation. Pro-arrhythmic implications of measured LV/RV functional differences were studied using in silico simulations. Results show that LV/RV APD and APD adaptation heterogeneities promote unidirectional block following rate acceleration, albeit being insufficient for establishment of reentry in normal hearts. However, in the presence of an ischemic region at the LV/RV junction, LV/RV heterogeneity in APD and APD rate adaptation promotes reentrant activity and its degeneration into fibrillatory activity. Our results suggest that LV/RV heterogeneities in APD adaptation cause a transient increase in APD dispersion in the human ventricles following rate acceleration, which promotes unidirectional block and wave-break at the LV/RV junction, and may potentiate the arrhythmogenic substrate, particularly in patients with ischemic heart disease. PMID:23284948

  9. Tests of GNSS receivers for dynamic, high sample rate response using controlled sources of displacement, velocity, and acceleration

    NASA Astrophysics Data System (ADS)

    Langbein, J. O.; Evans, J. R.; Blume, F.; Johanson, I. A.

    2012-12-01

    Global Navigational Satellite Systems (GNSS) are being employed to augment seismic instrumentation to record large, dynamic displacements and accelerations from large earthquakes. To date, however, there have been only a few tests that independently characterize the GNSS at frequencies and displacements that occur during large earthquakes (a number of error sources might influence such GPS result, including loss of lock or bias in signal tracking loops). Many of these tests consist of replaying the observed accelerations for select earthquakes recorded by seismic instruments through a shake-table on which a GNSS antenna is attached. Then the derived displacement from the accelerometer is compared with the displacement estimated from the GNSS system, or the GNSS derived acceleration is compared with the acceleration of the shake table. Neither comparison is optimal since derived quantities are used, and in particular, displacements derived from acceleration data have many sources of error at long periods. Another approach is to test the response of the GNSS receiver using a GNSS-simulator where synthetic GNSS signals are generated that mimic the signals that are actually received. Ebinuma and Kato (Earth Planet Space, 2012) describe a series of controlled tests using this approach with three different GNSS receivers. As a "real world" test, we performed similar experiments using a shake table, in open air with normal views of GNSS satellites, with controlled displacement inputs but, importantly, measured the displacement and acceleration of this table independently. We used a single-axis shake-table having up to 40 cm horizontal displacement and independently measured the position of the stage to better than 0.1 mm (from table servo loop optical reference; accelerations measured by accelerometers attached to moving part of stage). We tested five different GNSS receivers recording both GPS and GLONASS at 50 samples per second (sps), with the exception of the Trimble

  10. Comparing Response Rates in E-Mail and Paper Surveys: A Meta-Analysis

    ERIC Educational Resources Information Center

    Shih, Tse-Hua; Fan, Xitao

    2009-01-01

    This meta-analysis examined 35 study results within last 10 years that directly compared the response rates of e-mail versus mail surveys. Individual studies reported inconsistent findings concerning the response rate difference between e-mail and mail surveys, but e-mail surveys generally have lower response rate (about 20% lower on the average)…

  11. Optimized ion acceleration using high repetition rate, variable thickness liquid crystal targets

    NASA Astrophysics Data System (ADS)

    Poole, Patrick; Willis, Christopher; Cochran, Ginevra; Andereck, C. David; Schumacher, Douglass

    2015-11-01

    Laser-based ion acceleration is a widely studied plasma physics topic for its applications to secondary radiation sources, advanced imaging, and cancer therapy. Recent work has centered on investigating new acceleration mechanisms that promise improved ion energy and spectrum. While the physics of these mechanisms is not yet fully understood, it has been observed to dominate for certain ranges of target thickness, where the optimum thickness depends on laser conditions including energy, pulse width, and contrast. The study of these phenomena is uniquely facilitated by the use of variable-thickness liquid crystal films, first introduced in P. L. Poole et al. PoP21, 063109 (2014). Control of the formation parameters of these freely suspended films such as volume, temperature, and draw speed allows on-demand thickness variability between 10 nanometers and several 10s of microns, fully encompassing the currently studied thickness regimes with a single target material. The low vapor pressure of liquid crystal enables in-situ film formation and unlimited vacuum use of these targets. Details on the selection and optimization of ion acceleration mechanism with target thickness will be presented, including recent experiments on the Scarlet laser facility and others. This work was performed with support from the DARPA PULSE program through a grant from AMRDEC and by the NNSA under contract DE-NA0001976.

  12. CCAP and FMRFamide-like peptides accelerate the contraction rate of the antennal accessory pulsatile organs (auxiliary hearts) of mosquitoes.

    PubMed

    Suggs, Julia M; Jones, Talitha H; Murphree, Steven C; Hillyer, Julián F

    2016-08-01

    Insects rely on specialized accessory pulsatile organs (APOs), also known as auxiliary hearts, to propel hemolymph into their antennae. In most insects, this is accomplished via the pulsations of a pair of ampulla located in the head, each of which propels hemolymph across an antenna via an antennal vessel. Once at the distal end of the appendage, hemolymph returns to the head via the antennal hemocoel. Although the structure of the antennal hearts has been elucidated in various insect orders, their hormonal modulation has only been studied in cockroaches and other hemimetabolous insects within the superorder Polyneoptera, where proctolin and FMRFamide-like peptides accelerate the contraction rate of these auxiliary hearts. Here, we assessed the hormonal modulation of the antennal APOs of mosquitoes, a group of holometabolous (Endopterygota) insects within the order Diptera. We show that crustacean cardioactive peptide (CCAP), FMRFamide and SALDKNFMRFamide increase the contraction rate of the antennal APOs and the heart of Anopheles gambiae Both antennal hearts are synchronously responsive to these neuropeptides, but their contractions are asynchronous with the contraction of the heart. Furthermore, we show that these neuropeptides increase the velocity and maximum acceleration of hemolymph within the antennal space, suggesting that each contraction is also more forceful. To our knowledge, this is the first report demonstrating that hormones of a holometabolous insect modulate the contraction dynamics of an auxiliary heart, and the first report that shows that the hormones of any insect accelerate the velocity of hemolymph in the antennal space. PMID:27247317

  13. The Impact of Back-Sputtered Carbon on the Accelerator Grid Wear Rates of the NEXT and NSTAR Ion Thrusters

    NASA Technical Reports Server (NTRS)

    Soulas, George C.

    2013-01-01

    A study was conducted to quantify the impact of back-sputtered carbon on the downstream accelerator grid erosion rates of the NASA's Evolutionary Xenon Thruster (NEXT) Long Duration Test (LDT1). A similar analysis that was conducted for the NASA's Solar Electric Propulsion Technology Applications Readiness Program (NSTAR) Life Demonstration Test (LDT2) was used as a foundation for the analysis developed herein. A new carbon surface coverage model was developed that accounted for multiple carbon adlayers before complete surface coverage is achieved. The resulting model requires knowledge of more model inputs, so they were conservatively estimated using the results of past thin film sputtering studies and particle reflection predictions. In addition, accelerator current densities across the grid were rigorously determined using an ion optics code to determine accelerator current distributions and an algorithm to determine beam current densities along a grid using downstream measurements. The improved analysis was applied to the NSTAR test results for evaluation. The improved analysis demonstrated that the impact of back-sputtered carbon on pit and groove wear rate for the NSTAR LDT2 was negligible throughout most of eroded grid radius. The improved analysis also predicted the accelerator current density for transition from net erosion to net deposition considerably more accurately than the original analysis. The improved analysis was used to estimate the impact of back-sputtered carbon on the accelerator grid pit and groove wear rate of the NEXT Long Duration Test (LDT1). Unlike the NSTAR analysis, the NEXT analysis was more challenging because the thruster was operated for extended durations at various operating conditions and was unavailable for measurements because the test is ongoing. As a result, the NEXT LDT1 estimates presented herein are considered preliminary until the results of future post-test analyses are incorporated. The worst-case impact of carbon

  14. The Impact of Back-Sputtered Carbon on the Accelerator Grid Wear Rates of the NEXT and NSTAR Ion Thrusters

    NASA Technical Reports Server (NTRS)

    Soulas, George C.

    2013-01-01

    A study was conducted to quantify the impact of back-sputtered carbon on the downstream accelerator grid erosion rates of the NEXT (NASA's Evolutionary Xenon Thruster) Long Duration Test (LDT1). A similar analysis that was conducted for the NSTAR (NASA's Solar Electric Propulsion Technology Applications Readiness Program) Life Demonstration Test (LDT2) was used as a foundation for the analysis developed herein. A new carbon surface coverage model was developed that accounted for multiple carbon adlayers before complete surface coverage is achieved. The resulting model requires knowledge of more model inputs, so they were conservatively estimated using the results of past thin film sputtering studies and particle reflection predictions. In addition, accelerator current densities across the grid were rigorously determined using an ion optics code to determine accelerator current distributions and an algorithm to determine beam current densities along a grid using downstream measurements. The improved analysis was applied to the NSTAR test results for evaluation. The improved analysis demonstrated that the impact of back-sputtered carbon on pit and groove wear rate for the NSTAR LDT2 was negligible throughout most of eroded grid radius. The improved analysis also predicted the accelerator current density for transition from net erosion to net deposition considerably more accurately than the original analysis. The improved analysis was used to estimate the impact of back-sputtered carbon on the accelerator grid pit and groove wear rate of the NEXT Long Duration Test (LDT1). Unlike the NSTAR analysis, the NEXT analysis was more challenging because the thruster was operated for extended durations at various operating conditions and was unavailable for measurements because the test is ongoing. As a result, the NEXT LDT1 estimates presented herein are considered preliminary until the results of future posttest analyses are incorporated. The worst-case impact of carbon back

  15. Light scattering microscopy measurements of single nuclei compared with GPU-accelerated FDTD simulations

    NASA Astrophysics Data System (ADS)

    Stark, Julian; Rothe, Thomas; Kieß, Steffen; Simon, Sven; Kienle, Alwin

    2016-04-01

    Single cell nuclei were investigated using two-dimensional angularly and spectrally resolved scattering microscopy. We show that even for a qualitative comparison of experimental and theoretical data, the standard Mie model of a homogeneous sphere proves to be insufficient. Hence, an accelerated finite-difference time-domain method using a graphics processor unit and domain decomposition was implemented to analyze the experimental scattering patterns. The measured cell nuclei were modeled as single spheres with randomly distributed spherical inclusions of different size and refractive index representing the nucleoli and clumps of chromatin. Taking into account the nuclear heterogeneity of a large number of inclusions yields a qualitative agreement between experimental and theoretical spectra and illustrates the impact of the nuclear micro- and nanostructure on the scattering patterns.

  16. Light scattering microscopy measurements of single nuclei compared with GPU-accelerated FDTD simulations.

    PubMed

    Stark, Julian; Rothe, Thomas; Kieß, Steffen; Simon, Sven; Kienle, Alwin

    2016-04-01

    Single cell nuclei were investigated using two-dimensional angularly and spectrally resolved scattering microscopy. We show that even for a qualitative comparison of experimental and theoretical data, the standard Mie model of a homogeneous sphere proves to be insufficient. Hence, an accelerated finite-difference time-domain method using a graphics processor unit and domain decomposition was implemented to analyze the experimental scattering patterns. The measured cell nuclei were modeled as single spheres with randomly distributed spherical inclusions of different size and refractive index representing the nucleoli and clumps of chromatin. Taking into account the nuclear heterogeneity of a large number of inclusions yields a qualitative agreement between experimental and theoretical spectra and illustrates the impact of the nuclear micro- and nanostructure on the scattering patterns. PMID:26976736

  17. Formulated collagen gel accelerates healing rate immediately after application in patients with diabetic neuropathic foot ulcers

    PubMed Central

    Blume, Peter; Driver, Vickie R; Tallis, Arthur J; Kirsner, Robert S; Kroeker, Roy; Payne, Wyatt G; Wali, Soma; Marston, William; Dove, Cyaandi; Engler, Robert L; Chandler, Lois A; Sosnowski, Barbara K

    2011-01-01

    We assessed the safety and efficacy of Formulated Collagen Gel (FCG) alone and with Ad5PDGF-B (GAM501) compared with Standard of Care (SOC) in patients with 1.5–10.0 cm2 chronic diabetic neuropathic foot ulcers that healed <30% during Run-in. Wound size was assessed by planimetry of acetate tracings and photographs in 124 patients. Comparison of data sets revealed that acetate tracings frequently overestimated areas at some sites. For per-protocol analysis, 113 patients qualified using acetate tracings but only 82 qualified using photographs. Prior animal studies suggested that collagen alone would have little effect on healing and would serve as a negative control. Surprisingly trends for increased incidence of complete closure were observed for both GAM501 (41%) and FCG (45%) vs. Standard of Care (31%). By photographic data, Standard of Care had no significant effect on change in wound radius (mm/week) from during Run-in to Week 1 (−0.06±0.32 to 0.78±1.53, p=ns) but both FCG (−0.08±0.61 to 1.97±1.77, p<0.002) and GAM501 (−0.02±0.58 to 1.46±1.37, p<0.002) significantly increased healing rates that gradually declined over subsequent weeks. Both GAM501 and FCG appeared to be safe and well tolerated, and alternate dosing schedules hold promise to improve overall complete wound closure in adequately powered trials. PMID:21371164

  18. Limitations of current dosimetry for intracavitary accelerated partial breast irradiation with high dose rate iridium-192 and electronic brachytherapy sources

    NASA Astrophysics Data System (ADS)

    Raffi, Julie A.

    Intracavitary accelerated partial breast irradiation (APBI) is a method of treating early stage breast cancer using a high dose rate (HDR) brachytherapy source positioned within the lumpectomy cavity. An expandable applicator stretches the surrounding tissue into a roughly spherical or elliptical shape and the dose is prescribed to 1 cm beyond the edge of the cavity. Currently, dosimetry for these treatments is most often performed using the American Association of Physicists in Medicine Task Group No. 43 (TG-43) formalism. The TG-43 dose-rate equation determines the dose delivered to a homogeneous water medium by scaling the measured source strength with standardized parameters that describe the radial and angular features of the dose distribution. Since TG-43 parameters for each source model are measured or calculated in a homogeneous water medium, the dosimetric effects of the patient's dimensions and composition are not accounted for. Therefore, the accuracy of TG-43 calculations for intracavitary APBI is limited by the presence of inhomogeneities in and around the target volume. Specifically, the breast is smaller than the phantoms used to determine TG-43 parameters and is surrounded by air, ribs, and lung tissue. Also, the composition of the breast tissue itself can affect the dose distribution. This dissertation is focused on investigating the limitations of TG-43 dosimetry for intracavitary APBI for two HDR brachytherapy sources: the VariSource TM VS2000 192Ir source and the AxxentRTM miniature x-ray source. The dose for various conditions was determined using thermoluminescent dosimeters (TLDs) and Monte Carlo (MC) calculations. Accurate measurements and calculations were achieved through the implementation of new measurement and simulation techniques and a novel breast phantom was developed to enable anthropomorphic phantom measurements. Measured and calculated doses for phantom and patient geometries were compared with TG-43 calculated doses to

  19. SU-E-T-495: Neutron Induced Electronics Failure Rate Analysis for a Single Room Proton Accelerator

    SciTech Connect

    Knutson, N; DeWees, T; Klein, E

    2014-06-01

    Purpose: To determine the failure rate as a function of neutron dose of the range modulator's servo motor controller system (SMCS) while shielded with Borated Polyethylene (BPE) and unshielded in a single room proton accelerator. Methods: Two experimental setups were constructed using two servo motor controllers and two motors. Each SMCS was then placed 30 cm from the end of the plugged proton accelerator applicator. The motor was then turned on and observed from outside of the vault while being irradiated to known neutron doses determined from bubble detector measurements. Anytime the motor deviated from the programmed motion a failure was recorded along with the delivered dose. The experiment was repeated using 9 cm of BPE shielding surrounding the SMCS. Results: Ten SMCS failures were recorded in each experiment. The dose per monitor unit for the unshielded SMCS was 0.0211 mSv/MU and 0.0144 mSv/MU for the shielded SMCS. The mean dose to produce a failure for the unshielded SMCS was 63.5 ± 58.3 mSv versus 17.0 ±12.2 mSv for the shielded. The mean number of MUs between failures were 2297 ± 1891 MU for the unshielded SMCS and 2122 ± 1523 MU for the shielded. A Wilcoxon Signed Ranked test showed the dose between failures were significantly different (P value = 0.044) while the number of MUs between failures were not (P value = 1.000). Statistical analysis determined a SMCS neutron dose of 5.3 mSv produces a 5% chance of failure. Depending on the workload and location of the SMCS, this failure rate could impede clinical workflow. Conclusion: BPE shielding was shown to not reduce the average failure of the SMCS and relocation of the system outside of the accelerator vault was required to lower the failure rate enough to avoid impeding clinical work flow.

  20. GTPase acceleration as the rate-limiting step in Arabidopsis G protein-coupled sugar signaling.

    PubMed

    Johnston, Christopher A; Taylor, J Philip; Gao, Yajun; Kimple, Adam J; Grigston, Jeffrey C; Chen, Jin-Gui; Siderovski, David P; Jones, Alan M; Willard, Francis S

    2007-10-30

    Heterotrimeric G protein signaling is important for cell-proliferative and glucose-sensing signal transduction pathways in the model plant organism Arabidopsis thaliana. AtRGS1 is a seven-transmembrane, RGS domain-containing protein that is a putative membrane receptor for d-glucose. Here we show, by using FRET, that d-glucose alters the interaction between the AtGPA1 and AtRGS1 in vivo. AtGPA1 is a unique heterotrimeric G protein alpha subunit that is constitutively GTP-bound given its high spontaneous nucleotide exchange coupled with slow GTP hydrolysis. Analysis of a point mutation in AtRGS1 that abrogates GTPase-accelerating activity demonstrates that the regulation of AtGPA1 GTP hydrolysis mediates sugar signal transduction during Arabidopsis development, in contrast to animals where nucleotide exchange is the limiting step in the heterotrimeric G protein nucleotide cycle. PMID:17951432

  1. Comparing transient, accelerated, and equilibrium simulations of the last 30 000 years with the GENIE-1 model

    NASA Astrophysics Data System (ADS)

    Lunt, D. J.; Williamson, M. S.; Valdes, P. J.; Lenton, T. M.

    2006-06-01

    We examine several aspects of the ocean-atmosphere system over the last 30 000 years, by carrying out simulations with prescribed ice-sheets, atmospheric CO2 concentration, and orbital parameters. We use the GENIE-1 model with a geostrophic ocean, dynamic sea-ice, an energy balance atmosphere, and a land-surface scheme with fixed vegetation. A transient simulation, with boundary conditions derived from ice-core records and ice-sheet reconstructions, is compared with equilibrium snapshot simulations, including the Last Glacial Maximum (21 000 years before present; 21 kyrBP), mid-Holocene (6 kyrBP) and pre-industrial. The equilibrium snapshot surface temperatures are all very similar to their corresponding time period in the transient simulation, suggesting that in the last 30 000 years, the ocean-atmosphere system has been close to equilibrium with its boundary conditions. We investigate the method of accelerating the boundary conditions of a transient simulation and find that the Southern Ocean is the region most affected by the acceleration. The Northern Hemisphere, even with a factor of 10 acceleration, is relatively unaffected.

  2. Electron diffraction using ultrafast electron bunches from a laser-wakefield accelerator at kHz repetition rate

    NASA Astrophysics Data System (ADS)

    He, Z.-H.; Thomas, A. G. R.; Beaurepaire, B.; Nees, J. A.; Hou, B.; Malka, V.; Krushelnick, K.; Faure, J.

    2013-02-01

    We show that electron bunches in the 50-100 keV range can be produced from a laser wakefield accelerator using 10 mJ, 35 fs laser pulses operating at 0.5 kHz. It is shown that using a solenoid magnetic lens, the electron bunch distribution can be shaped. The resulting transverse and longitudinal coherence is suitable for producing diffraction images from a polycrystalline 10 nm aluminum foil. The high repetition rate, the stability of the electron source, and the fact that its uncorrelated bunch duration is below 100 fs make this approach promising for the development of sub-100 fs ultrafast electron diffraction experiments.

  3. A Follow-Up Study to Compare Success Rates of Developmental Math Students

    ERIC Educational Resources Information Center

    Woodard, Teresa; Burkett, Sexton

    2010-01-01

    This article presents a study that compared the success rates of students in Arithmetic (MTH 02), Algebra I (MTH 03), and Algebra II (MTH 03) when they were offered at Southwest Virginia Community College (SWCC) for three credits versus five credits. The authors' findings showed no significant differences in the success rates of students who were…

  4. Peer Assessment in the Digital Age: A Meta-Analysis Comparing Peer and Teacher Ratings

    ERIC Educational Resources Information Center

    Li, Hongli; Xiong, Yao; Zang, Xiaojiao; Kornhaber, Mindy L.; Lyu, Youngsun; Chung, Kyung Sun; Suen, Hoi K.

    2016-01-01

    Given the wide use of peer assessment, especially in higher education, the relative accuracy of peer ratings compared to teacher ratings is a major concern for both educators and researchers. This concern has grown with the increase of peer assessment in digital platforms. In this meta-analysis, using a variance-known hierarchical linear modelling…

  5. Comparing Enrollment and Persistence Rates in Hybrid and Traditional Post-Secondary French

    ERIC Educational Resources Information Center

    Gascoigne, Carolyn; Parnell, Juliette

    2014-01-01

    Persistence rates in foreign language study have been historically disappointing. This also tends to be the case for many hybrid and online courses, especially when contrasted with comparable face-to-face courses. Therefore, when transitioning foreign language coursework to online and hybrid formats, increased persistence rates and a large number…

  6. Improving Survey Response Rates of School Counselors: Comparing the Use of Incentives

    ERIC Educational Resources Information Center

    Bauman, Sheri

    2007-01-01

    This article examines the effectiveness of incentives in improving survey response rates of school counselors and compares the findings with those of previously researched populations. A $1 cash incentive increased response rates for a one-wave mailing of a questionnaire, while a raffle opportunity did not. The number and length of optional…

  7. Insulin accelerates global and mitochondrial protein synthesis rates in neonatal muscle during sepsis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In neonatal pigs, sepsis decreases protein synthesis in skeletal muscle by decreasing translation initiation. However, insulin stimulates muscle protein synthesis despite persistent repression of translation initiation signaling. To determine whether the insulin-induced increase in global rates of m...

  8. Surface composition and barium evaporation rate of ``pedigreed'' impregnated tungsten dispenser cathodes during accelerated life testing

    NASA Astrophysics Data System (ADS)

    Tomich, D. H.; Mescher, J. A.; Grant, J. T.

    1987-03-01

    A study has been made of the surface composition and barium evaporation rate of "pedigreed" impregnated tungsten dispenser cathodes. The effect of air exposure on coated cathodes was examined and was found to have no significant effect on barium evaporation rate although in some cases longer reactivation times were required. No changes in surface topography were apparent following air exposure and reactivation. Life testing was done at 100°C above the typical operating temperature for the cathode, where the typical operating temperature was taken to be 950°C for coated cathodes and 1050°C for uncoated cathodes. The cathodes were examined at different stages of life testing, up to 1200 h. Significant decreases in barium evaporation rates were found after as few as 500 h of life testing. After 1000 h the evaporation rate had decreased more than an order of magnitude. Changes in surface composition were also found. The effects of tungsten particle size, used in manufacture of the billet, on barium evaporation rate were also studied but no correlation was found.

  9. Coevolution within and between Regulatory Loci Can Preserve Promoter Function Despite Evolutionary Rate Acceleration

    PubMed Central

    Barrière, Antoine; Gordon, Kacy L.; Ruvinsky, Ilya

    2012-01-01

    Phenotypes that appear to be conserved could be maintained not only by strong purifying selection on the underlying genetic systems, but also by stabilizing selection acting via compensatory mutations with balanced effects. Such coevolution has been invoked to explain experimental results, but has rarely been the focus of study. Conserved expression driven by the unc-47 promoters of Caenorhabditis elegans and C. briggsae persists despite divergence within a cis-regulatory element and between this element and the trans-regulatory environment. Compensatory changes in cis and trans are revealed when these promoters are used to drive expression in the other species. Functional changes in the C. briggsae promoter, which has experienced accelerated sequence evolution, did not lead to alteration of gene expression in its endogenous environment. Coevolution among promoter elements suggests that complex epistatic interactions within cis-regulatory elements may facilitate their divergence. Our results offer a detailed picture of regulatory evolution in which subtle, lineage-specific, and compensatory modifications of interacting cis and trans regulators together maintain conserved gene expression patterns. PMID:23028368

  10. Accelerating Struggling Readers' Progress: A Comparative Analysis of Expert Opinion and Current Research Recommendations

    ERIC Educational Resources Information Center

    Reutzel, D. Ray; Smith, John A.

    2004-01-01

    In this article, we review the findings of Rona Flippo's (1998) "Expert Study" within the comparative context of recently published reading research reports such as the National Reading Panel report (National Institute of Child Health and Human Development, 2000) and Preventing Reading Difficulties in Young Children (Snow, Burns, & Griffin, 1998).…

  11. Membrane Tension Accelerates Rate-limiting Voltage-dependent Activation and Slow Inactivation Steps in a Shaker Channel

    PubMed Central

    Laitko, Ulrike; Morris, Catherine E.

    2004-01-01

    A classical voltage-sensitive channel is tension sensitive—the kinetics of Shaker and S3–S4 linker deletion mutants change with membrane stretch (Tabarean, I.V., and C.E. Morris. 2002. Biophys. J. 82:2982–2994.). Does stretch distort the channel protein, producing novel channel states, or, more interestingly, are existing transitions inherently tension sensitive? We examined stretch and voltage dependence of mutant 5aa, whose ultra-simple activation (Gonzalez, C., E. Rosenman, F. Bezanilla, O. Alvarez, and R. Latorre. 2000. J. Gen. Physiol. 115:193–208.) and temporally matched activation and slow inactivation were ideal for these studies. We focused on macroscopic patch current parameters related to elementary channel transitions: maximum slope and delay of current rise, and time constant of current decline. Stretch altered the magnitude of these parameters, but not, or minimally, their voltage dependence. Maximum slope and delay versus voltage with and without stretch as well as current rising phases were well described by expressions derived for an irreversible four-step activation model, indicating there is no separate stretch-activated opening pathway. This model, with slow inactivation added, explains most of our data. From this we infer that the voltage-dependent activation path is inherently stretch sensitive. Simulated currents for schemes with additional activation steps were compared against datasets; this showed that generally, additional complexity was not called for. Because the voltage sensitivities of activation and inactivation differ, it was not possible to substitute depolarization for stretch so as to produce the same overall PO time course. What we found, however, was that at a given voltage, stretch-accelerated current rise and decline almost identically—normalized current traces with and without stretch could be matched by a rescaling of time. Rate-limitation of the current falling phase by activation was ruled out. We hypothesize

  12. Membrane tension accelerates rate-limiting voltage-dependent activation and slow inactivation steps in a Shaker channel.

    PubMed

    Laitko, Ulrike; Morris, Catherine E

    2004-02-01

    A classical voltage-sensitive channel is tension sensitive--the kinetics of Shaker and S3-S4 linker deletion mutants change with membrane stretch (Tabarean, I.V., and C.E. Morris. 2002. Biophys. J. 82:2982-2994.). Does stretch distort the channel protein, producing novel channel states, or, more interestingly, are existing transitions inherently tension sensitive? We examined stretch and voltage dependence of mutant 5aa, whose ultra-simple activation (Gonzalez, C., E. Rosenman, F. Bezanilla, O. Alvarez, and R. Latorre. 2000. J. Gen. Physiol. 115:193-208.) and temporally matched activation and slow inactivation were ideal for these studies. We focused on macroscopic patch current parameters related to elementary channel transitions: maximum slope and delay of current rise, and time constant of current decline. Stretch altered the magnitude of these parameters, but not, or minimally, their voltage dependence. Maximum slope and delay versus voltage with and without stretch as well as current rising phases were well described by expressions derived for an irreversible four-step activation model, indicating there is no separate stretch-activated opening pathway. This model, with slow inactivation added, explains most of our data. From this we infer that the voltage-dependent activation path is inherently stretch sensitive. Simulated currents for schemes with additional activation steps were compared against datasets; this showed that generally, additional complexity was not called for. Because the voltage sensitivities of activation and inactivation differ, it was not possible to substitute depolarization for stretch so as to produce the same overall PO time course. What we found, however, was that at a given voltage, stretch-accelerated current rise and decline almost identically--normalized current traces with and without stretch could be matched by a rescaling of time. Rate-limitation of the current falling phase by activation was ruled out. We hypothesize, therefore

  13. HDRMC, an accelerated Monte Carlo dose calculator for high dose rate brachytherapy with CT-compatible applicators

    SciTech Connect

    Chibani, Omar C-M Ma, Charlie

    2014-05-15

    Purpose: To present a new accelerated Monte Carlo code for CT-based dose calculations in high dose rate (HDR) brachytherapy. The new code (HDRMC) accounts for both tissue and nontissue heterogeneities (applicator and contrast medium). Methods: HDRMC uses a fast ray-tracing technique and detailed physics algorithms to transport photons through a 3D mesh of voxels representing the patient anatomy with applicator and contrast medium included. A precalculated phase space file for the{sup 192}Ir source is used as source term. HDRM is calibrated to calculated absolute dose for real plans. A postprocessing technique is used to include the exact density and composition of nontissue heterogeneities in the 3D phantom. Dwell positions and angular orientations of the source are reconstructed using data from the treatment planning system (TPS). Structure contours are also imported from the TPS to recalculate dose-volume histograms. Results: HDRMC was first benchmarked against the MCNP5 code for a single source in homogenous water and for a loaded gynecologic applicator in water. The accuracy of the voxel-based applicator model used in HDRMC was also verified by comparing 3D dose distributions and dose-volume parameters obtained using 1-mm{sup 3} versus 2-mm{sup 3} phantom resolutions. HDRMC can calculate the 3D dose distribution for a typical HDR cervix case with 2-mm resolution in 5 min on a single CPU. Examples of heterogeneity effects for two clinical cases (cervix and esophagus) were demonstrated using HDRMC. The neglect of tissue heterogeneity for the esophageal case leads to the overestimate of CTV D90, CTV D100, and spinal cord maximum dose by 3.2%, 3.9%, and 3.6%, respectively. Conclusions: A fast Monte Carlo code for CT-based dose calculations which does not require a prebuilt applicator model is developed for those HDR brachytherapy treatments that use CT-compatible applicators. Tissue and nontissue heterogeneities should be taken into account in modern HDR

  14. Ancient dates or accelerated rates? Morphological clocks and the antiquity of placental mammals

    PubMed Central

    Beck, Robin M. D.; Lee, Michael S. Y.

    2014-01-01

    Analyses of a comprehensive morphological character matrix of mammals using ‘relaxed’ clock models (which simultaneously estimate topology, divergence dates and evolutionary rates), either alone or in combination with an 8.5 kb nuclear sequence dataset, retrieve implausibly ancient, Late Jurassic–Early Cretaceous estimates for the initial diversification of Placentalia (crown-group Eutheria). These dates are much older than all recent molecular and palaeontological estimates. They are recovered using two very different clock models, and regardless of whether the tree topology is freely estimated or constrained using scaffolds to match the current consensus placental phylogeny. This raises the possibility that divergence dates have been overestimated in previous analyses that have applied such clock models to morphological and total evidence datasets. Enforcing additional age constraints on selected internal divergences results in only a slight reduction of the age of Placentalia. Constraining Placentalia to less than 93.8 Ma, congruent with recent molecular estimates, does not require major changes in morphological or molecular evolutionary rates. Even constraining Placentalia to less than 66 Ma to match the ‘explosive’ palaeontological model results in only a 10- to 20-fold increase in maximum evolutionary rate for morphology, and fivefold for molecules. The large discrepancies between clock- and fossil-based estimates for divergence dates might therefore be attributable to relatively small changes in evolutionary rates through time, although other explanations (such as overly simplistic models of morphological evolution) need to be investigated. Conversely, dates inferred using relaxed clock models (especially with discrete morphological data and MrBayes) should be treated cautiously, as relatively minor deviations in rate patterns can generate large effects on estimated divergence dates. PMID:25165770

  15. Selective sinoatrial node optical mapping to investigate the mechanism of sinus rate acceleration

    NASA Astrophysics Data System (ADS)

    Lin, Shien-Fong; Shinohara, Tetsuji; Joung, Boyoung; Chen, Peng-Sheng

    2011-03-01

    Studies using isolated sinoatrial node (SAN) cells indicate that rhythmic spontaneous sarcoplasmic reticulum Ca release (Ca clock) plays an important role in SAN automaticity. However, it is difficult to translate these findings into intact SAN because the SAN is embedded in the right atrium (RA). Cross contamination of the optical signals between SAN and RA prevented the definitive testing of Ca clock hypothesis in intact SAN. We use a novel approach to selectively map intact SAN to examine the Ca clock function in intact RA. We simultaneously mapped intracellular Ca (Cai) and membrane potential (Vm) in 7 isolated, Langendorff perfused normal canine RA. Electrical conduction from the SAN to RA was inhibited with high potassium (10 mmol/L) Tyrode's solution, allowing selective optical mapping of Vm and Cai of the SAN. Isoproterenol (ISO, 0.03 μmol/L) decreased cycle length of the sinus beats from 586+/-17 ms at baseline to 366+/-32 ms, and shifted the leading pacemaker site from the middle or inferior SAN to the superior SAN in all RAs. The Cai upstroke preceded the Vm in the leading pacemaker site by up to 18+/-2 ms. ISO-induced changes to SAN were inhibited by ryanodine (3 μmol/L), but not ZD7288 (3 μmol/L), a selective If blocker. We conclude that a high extracellular potassium concentration results in intermittent SAN-RA conduction block, allowing selective optical mapping of the intact SAN. Acceleration of Ca cycling in the superior SAN underlies the mechanism of sinus tachycardia during sympathetic stimulation.

  16. UVB Exposure Does Not Accelerate Rates of Litter Decomposition in a Semiarid Riparian Ecosystem

    NASA Astrophysics Data System (ADS)

    Uselman, S. M.; Snyder, K. A.; Blank, R. R.; Jones, T. J.

    2010-12-01

    Aboveground litter decomposition is controlled mainly by substrate quality and climate factors across terrestrial ecosystems, but photodegradation from exposure to high-intensity ultraviolet-B (UVB) radiation may also be important in arid and semi-arid environments. We investigated the interactive effects of UVB exposure and litter quality on decomposition in a Tamarix-invaded riparian ecosystem during the establishment of an insect biological control agent in northern Nevada. Feeding by the northern tamarisk beetle (Diorhabda carinulata) on Tamarix spp. trees leads to altered leaf litter quality and increased exposure to solar UVB radiation from canopy opening. In addition, we examined the dynamics of litter decomposition of the invasive exotic Lepidium latifolium, because it is well-situated to invade beetle-infested Tamarix sites. Three leaf litter types (natural Tamarix, beetle-affected Tamarix, and L. latifolium) differing in substrate quality were decomposed in litterbags for one year in the field. Litterbags were subjected to one of three treatments: (1) Ambient UVB or (2) Reduced UVB (where UVB was manipulated by using clear plastic films that transmit or block UVB), and (3) No Cover (a control used to test for the effect of using the plastic films, i.e. a cover effect). Results showed a large cover effect on rates of decomposition and nutrient release, and our findings suggested that frequent cycles of freeze-thaw, and possibly rainfall intensity, influenced decomposition at this site. Contrary to our expectations, greater UVB exposure did not result in faster rates of decomposition. Greater UVB exposure resulted in decreased rates of decomposition and P release for the lower quality litter and no change in rates of decomposition and nutrient release for the two higher quality litter types, possibly due to a negative effect of UVB on soil microbes. Among litter types, rates of decomposition and net release of N and P followed this ranking: L. latifolium

  17. The Hanford Site generic component failure-rate database compared with other generic failure-rate databases

    SciTech Connect

    Reardon, M.F.; Zentner, M.D.

    1992-11-01

    The Risk Assessment Technology Group, Westinghouse Hanford Company (WHC), has compiled a component failure rate database to be used during risk and reliability analysis of nonreactor facilities. Because site-specific data for the Hanford Site are generally not kept or not compiled in a usable form, the database was assembled using information from a variety of other established sources. Generally, the most conservative failure rates were chosen from the databases reviewed. The Hanford Site database has since been used extensively in fault tree modeling of many Hanford Site facilities and systems. The purpose of this study was to evaluate the reasonableness of the data chosen for the Hanford Site database by comparing the values chosen with the values from the other databases.

  18. Plasma accelerators

    SciTech Connect

    Ruth, R.D.; Chen, P.

    1986-03-01

    In this paper we discuss plasma accelerators which might provide high gradient accelerating fields suitable for TeV linear colliders. In particular we discuss two types of plasma accelerators which have been proposed, the Plasma Beat Wave Accelerator and the Plasma Wake Field Accelerator. We show that the electric fields in the plasma for both schemes are very similar, and thus the dynamics of the driven beams are very similar. The differences appear in the parameters associated with the driving beams. In particular to obtain a given accelerating gradient, the Plasma Wake Field Accelerator has a higher efficiency and a lower total energy for the driving beam. Finally, we show for the Plasma Wake Field Accelerator that one can accelerate high quality low emittance beams and, in principle, obtain efficiencies and energy spreads comparable to those obtained with conventional techniques.

  19. Particle Rate and Host Accelerator Beam Loss on the MICE Experiment

    SciTech Connect

    Dobbs, Adam James

    2011-10-01

    A study is presented of particle rates in the MICE Muon Beamline and their relationship to beam loss produced in ISIS. A brief overview of neutrino physics is presented, together with a discussion on the Neutrino Factory as a motivation for MICE. An overview of MICE itself is then presented, highlighting the need for a systematic understanding of the relationship between the MICE target parameters, ISIS beam loss, and MICE particle rate. The variation of beam loss with target depth is examined and observed to be non-linear. The variation of beam loss with respect to the target dip time in the ISIS cycle is examined and observed to be approximately linear for dip times between 11.1 ms and 12.6 ms after ISIS injection, before tailing at earlier dip times. The variation of beam loss with particle rate is also observed to follow an approximately linear relationship from 0.05 V.ms to 4.7 V.ms beam loss, with a further strong indication that this continues up to 7.1 V.ms. Particle identification using time-of-flight data is used to give an insight into the relative abundances of each particle species present in the MICE beam. Estimates of muon rate are then produced as a function of beam loss. At a level of 2 V.ms beam loss ~10:9 muons per spill for a 3.2 ms spill with negative π → μ optics, and ~31:1 muons per 1 ms spill with positive π → μ optics are observed. Simulations using the ORBIT particle tracking code of the beam loss distributions around the ISIS ring, caused by the MICE target, are also presented and the implications for MICE running discussed.

  20. The complete plastid genome sequence of Welwitschia mirabilis: an unusually compact plastome with accelerated divergence rates

    PubMed Central

    2008-01-01

    Background Welwitschia mirabilis is the only extant member of the family Welwitschiaceae, one of three lineages of gnetophytes, an enigmatic group of gymnosperms variously allied with flowering plants or conifers. Limited sequence data and rapid divergence rates have precluded consensus on the evolutionary placement of gnetophytes based on molecular characters. Here we report on the first complete gnetophyte chloroplast genome sequence, from Welwitschia mirabilis, as well as analyses on divergence rates of protein-coding genes, comparisons of gene content and order, and phylogenetic implications. Results The chloroplast genome of Welwitschia mirabilis [GenBank: EU342371] is comprised of 119,726 base pairs and exhibits large and small single copy regions and two copies of the large inverted repeat (IR). Only 101 unique gene species are encoded. The Welwitschia plastome is the most compact photosynthetic land plant plastome sequenced to date; 66% of the sequence codes for product. The genome also exhibits a slightly expanded IR, a minimum of 9 inversions that modify gene order, and 19 genes that are lost or present as pseudogenes. Phylogenetic analyses, including one representative of each extant seed plant lineage and based on 57 concatenated protein-coding sequences, place Welwitschia at the base of all seed plants (distance, maximum parsimony) or as the sister to Pinus (the only conifer representative) in a monophyletic gymnosperm clade (maximum likelihood, bayesian). Relative rate tests on these gene sequences show the Welwitschia sequences to be evolving at faster rates than other seed plants. For these genes individually, a comparison of average pairwise distances indicates that relative divergence in Welwitschia ranges from amounts about equal to other seed plants to amounts almost three times greater than the average for non-gnetophyte seed plants. Conclusion Although the basic organization of the Welwitschia plastome is typical, its compactness, gene content

  1. Hillslope-channel coupling in a steep Hawaiian catchment accelerates erosion rates over 100-fold

    NASA Astrophysics Data System (ADS)

    Stock, J. D.; Hanshaw, M. N.; Rosener, M.; Schmidt, K. M.; Brooks, B. A.; Tribble, G.; Jacobi, J.

    2009-12-01

    In tropical watersheds, hillslope changes are producing increasing amounts of fine sediment that can be quickly carried to reefs by channels. Suspended sediment concentrations off the reefs of Molokai, Hawaii, chronically exceed a toxic level of 10 mg/L, threatening reef ecosystems. We hypothesize that historic conversion of watersheds from soil creep to overland flow erosion increased both magnitude and frequency of sediment flooding adjacent reefs. We combined surficial and ecological mapping, hillslope and stream gages, and novel sensors to locate, quantify and model the generation of fine sediments polluting the Molokai reef. Ecological and geomorphic mapping from LiDAR and multi-spectral imagery located a subset of overland flow areas with vegetation cover below a threshold value preventing erosion. Here, feral goat grazing exposed cohesive volcanic soils whose low matrix hydraulic conductivities (1-20 mm/hour) promote Horton overland flow erosion. We instrumented steep, barren hillslopes with soil moisture sensors, overland flow meters, Parshall flumes, ISCO sediment samplers, and a rain gage and conducted repeat Tripod LiDAR and infiltration tests. To characterize soil resistance here and elsewhere to overland flow erosion, we deployed a Cohesive Strength Meter (CSM) to simulate the stresses of flowing water. At the 13.5 km 2 watershed mouth we used a USGS stream gage and ISCO sediment sampler to estimate total load. Over 2 years, storms triggered overland flow during rainfall intensities above 10-15 mm/hr. Overland flow meters indicate such flows can be up to 3 cm deep, with a tendency to deepen downslope. CSM tests indicate that these depths are insufficient to erode soils where vegetation is dense, but far above threshold values of 2-3 mm depth for bare soil erosion. Sediment ratings curves for both hillslope and downstream catchment gages show strong clock-wise hysteresis during the first intense storms in the Fall, becoming linear later in the rainy

  2. A proposal to protect privacy of health information while accelerating comparative effectiveness research.

    PubMed

    Peddicord, Douglas; Waldo, Ann B; Boutin, Marc; Grande, Tina; Gutierrez, Luis

    2010-11-01

    Current laws, practices, and concerns about privacy inhibit access to health data for research. Barriers include inconsistent Institutional Review Board policies and complicated and costly procedures to obtain the consent of patients for release of their information. To realize the promise of comparative effectiveness research, it is essential to develop a new policy framework that will allow and encourage the use of health information in all forms--fully identifiable, partially anonymized, and deidentified. We propose that health data be made available for information-based research under a so-called research safe harbor. The arrangement would include strict data security controls, standards, and practices to be promulgated by the secretary of health and human services, and an annual third-party audit to ensure compliance. PMID:21041752

  3. Comparing transient, accelerated, and equilibrium simulations of the last 30 000 years with the GENIE-1 model

    NASA Astrophysics Data System (ADS)

    Lunt, D. J.; Williamson, M. S.; Valdes, P. J.; Lenton, T. M.; Marsh, R.

    2006-11-01

    We examine several aspects of the ocean-atmosphere system over the last 30 000 years, by carrying out simulations with prescribed ice sheets, atmospheric CO2 concentration, and orbital parameters. We use the GENIE-1 model with a frictional geostrophic ocean, dynamic sea ice, an energy balance atmosphere, and a land-surface scheme with fixed vegetation. A transient simulation, with boundary conditions derived from ice-core records and ice sheet reconstructions, is compared with equilibrium snapshot simulations, including the Last Glacial Maximum (21 000 years before present; 21 kyrBP), mid-Holocene (6 kyrBP) and pre-industrial. The equilibrium snapshot simulations are all very similar to their corresponding time period in the transient simulation, indicating that over the last 30 000 years, the model's ocean-atmosphere system is close to equilibrium with its boundary conditions. However, our simulations neglect the transfer of fresh water from and to the ocean, resulting from the growth and decay of ice sheets, which would, in reality, lead to greater disequilibrium. Additionally, the GENIE-1 model exhibits a rather limited response in terms of its Atlantic Meridional Overturning Circulation (AMOC) over the 30 000 years; a more sensitive AMOC would also be likely to lead to greater disequilibrium. We investigate the method of accelerating the boundary conditions of a transient simulation and find that the Southern Ocean is the region most affected by the acceleration. The Northern Hemisphere, even with a factor of 10 acceleration, is relatively unaffected. The results are robust to changes to several tunable parameters in the model. They also hold when a higher vertical resolution is used in the ocean.

  4. Comparison of the Effects of Two Auditory Methods by Mother and Fetus on the Results of Non-Stress Test (Baseline Fetal Heart Rate and Number of Accelerations) in Pregnant Women: A Randomized Controlled Trial

    PubMed Central

    Khoshkholgh, Roghaie; Keshavarz, Tahereh; Moshfeghy, Zeinab; Akbarzadeh, Marzieh; Asadi, Nasrin; Zare, Najaf

    2016-01-01

    Objective: To compare the effects of two auditory methods by mother and fetus on the results of NST in 2011-2012. Materials and methods: In this single-blind clinical trial, 213 pregnant women with gestational age of 37-41 weeks who had no pregnancy complications were randomly divided into 3 groups (auditory intervention for mother, auditory intervention for fetus, and control) each containing 71 subjects. In the intervention groups, music was played through the second 10 minutes of NST. The three groups were compared regarding baseline fetal heart rate and number of accelerations in the first and second 10 minutes of NST. The data were analyzed using one-way ANOVA, Kruskal-Wallis, and paired T-test. Results: The results showed no significant difference among the three groups regarding baseline fetal heart rate in the first (p = 0.945) and second (p = 0.763) 10 minutes. However, a significant difference was found among the three groups concerning the number of accelerations in the second 10 minutes. Also, a significant difference was observed in the number of accelerations in the auditory intervention for mother (p = 0.013) and auditory intervention for fetus groups (p < 0.001). The difference between the number of accelerations in the first and second 10 minutes was also statistically significant (p = 0.002). Conclusion: Music intervention was effective in the number of accelerations which is the indicator of fetal health. Yet, further studies are required to be conducted on the issue. PMID:27385971

  5. Can student self-ratings be compared with peer ratings? A study of measurement invariance of multisource feedback.

    PubMed

    Lee, Keng-Lin; Tsai, Shih-Li; Chiu, Yu-Ting; Ho, Ming-Jung

    2016-05-01

    Measurement invariance is a prerequisite for comparing measurement scores from different groups. In medical education, multi-source feedback (MSF) is utilized to assess core competencies, including the professionalism. However, little attention has been paid to the measurement invariance of assessment instruments; that is, whether an instrument holds the same meaning across different rater groups. To examine the measurement invariance of the National Taiwan University professionalism MSF (NTU P-MSF) in order to determine whether medical students' self-rating can be compared to their peers' rating. An eight-factor model was specified for confirmatory factor analysis to examine the construct validity of the NTU P-MSF. Cronbach's alpha was computed for the items of each domain to evaluate internal consistent reliability. The same eight-factor model was used for multi-group confirmatory factor analyses. Four hierarchical models were specified to test configural (i.e., identical factor-item relationship), metric (i.e., identical factor loadings), scalar (i.e., identical intercepts), and error variance across self-rating and peer rating groups. One hundred and twenty second-year medical students from weekly discussion groups conducted as part of a medical professionalism course agreed to use the NTU P-MSF to assess themselves or their discussion group peers. NTU P-MSF assessment scores were a good fit for the eight-factor model among self group and peer group. The Cronbach's alpha coefficients of students' NTU P-MSF scores and peers' scores ranged from 0.76 to 0.89 and 0.84 to 0.91, respectively indicating that the NTU P-MSF scores also have good internal consistent reliability between both groups. In addition, same factor structure and similar factor loadings and intercepts of NTU P-MSF scores between both groups indicate that NTU P-MSF scores had configural, metric, and scalar invariance. Thus, students' self-assessments and peer assessments can be compared in terms of

  6. Biogeochemical implications of comparative growth rates of Emiliania huxleyi and Coccolithus species

    NASA Astrophysics Data System (ADS)

    Daniels, C. J.; Sheward, R. M.; Poulton, A. J.

    2014-12-01

    Coccolithophores, a diverse group of phytoplankton, make important contributions to pelagic calcite production and export, yet the comparative biogeochemical role of species other than the ubiquitous Emiliania huxleyi is poorly understood. The contribution of different coccolithophore species to total calcite production is controlled by inter-species differences in cellular calcite, growth rate and relative abundance within a mixed community. In this study we examined the relative importance of E. huxleyi and two Coccolithus species in terms of daily calcite production. Culture experiments compared growth rates and cellular calcite content of E. huxleyi (Arctic and temperate strains), Coccolithus pelagicus (novel Arctic strain) and Coccolithus braarudii (temperate strain). Despite assumptions that E. huxleyi is a fast-growing species, growth rates between the three species were broadly comparable (0.16-0.85 d-1) under identical temperature and light conditions. Emiliania huxleyi grew only 12% faster on average than C. pelagicus, and 28% faster than C. braarudii. As the cellular calcite content of C. pelagicus and C. braarudii is typically 30-80 times greater than E. huxleyi, comparable growth rates suggest that Coccolithus species have the potential to be major calcite producers in mixed populations. To further explore these results we devised a simplistic model comparing daily calcite production from Coccolithus and E. huxleyi across a realistic range of relative abundances and a wide range of relative growth rates. Using the relative differences in growth rates from our culture studies, we found that C. pelagicus would be a larger source of calcite if abundances of E. huxleyi to C. pelagicus were below 34:1. Relative abundance data collected from North Atlantic field samples (spring and summer 2010) suggest that, with a relative growth rate of 88%, C. pelagicus dominated calcite production at 69% of the sites sampled. With a more extreme difference in growth

  7. Accelerating Rates of Discontinuous Permafrost Thaw Associated with Ground Surface Morphology and Changing Vegetation Structures Determined from Multi-Temporal LIDAR Data

    NASA Astrophysics Data System (ADS)

    Chasmer, L.; Hopkinson, C.

    2015-12-01

    Rates of permafrost thaw within the discontinuous permafrost zone are expected to accelerate with permafrost fragmentation. However quantification of drivers of permafrost change remain elusive due to the non-linearity of feedbacks in space and time. Given the extent of permafrost in Canada, there is significant interest in the mechanisms associated with land cover change as climate change and disturbance intensifies.We quantify the variability of rates of thaw associated with structural characteristics of the land surface within a discontinuous permafrost watershed in the NWT, Canada. Results are compared to an isolated permafrost watershed in Alberta, which may exemplify the northern discontinuous landscape in ~350 years. Three airborne Light Detection And Ranging (LiDAR) datasets have been collected in 2008, 2011 and 2015, coincident with digital photogrammetry (2008), thermal infrared (2011) and bathymetry (2015) within both watersheds. Rates of change of land elevation associated with permafrost thaw within plateaus and peatlands are quantified using non-linear spatial regression, and compared with topographic and vegetation derivatives. Results indicate that increasing fragmentation of discontinuous permafrost plateaus results in exponential thaw. Rates of thaw become linear with decreasing complexity. Accelerating thaw is related to substantial Picea mariana mortality (up to 45%), increased gap fraction within 1-2 m of plateau edges, and shrub succession (average growth ~0.2 m yr—1) at the 0-2m boundary within the 7-year period. Thaw rate in parts is also complicated by understory succession within the area of local convexity between the plateau and slope edge and linear thaw pathways. Greatest rates of thaw and vegetation mortality (~30-50%) are found on plateaus with populous tremuloides. In the central boreal watershed, vegetation succession at peatland margins is associated with increased drying and changes to runoff trends over the last 40 years

  8. High rates of carbon storage in old deciduous forests: Emerging mechanisms from the Forest Accelerated Succession ExperimenT (FASET)

    NASA Astrophysics Data System (ADS)

    Gough, C. M.; Nave, L. E.; Hardiman, B. S.; Bohrer, G.; Halperin, A.; Maurer, K.; Le Moine, J.; Nadelhoffer, K.; Vogel, C. S.; Curtis, P.; University Of Michigan Biological Station Forest Ecosystem Study (Umbs-Fest) Team

    2010-12-01

    Deciduous forests of the eastern US are broadly approaching an ecological threshold in which early successional dominant trees are senescing and giving way to later successional species, with unknown consequences for regional carbon (C) cycling. Though recent research demonstrates that forests may accumulate C for centuries, the mechanisms behind sustained rates of C storage in old, particularly deciduous, forests have not been identified. In a regionally representative forest at the University of Michigan Biological Station, we are combining observational and experimental C cycling studies to forecast how forest C storage responds to climate variation, disturbance, and succession. The Forest Accelerated Succession ExperimenT (FASET), in which >6,700 aspen and birch trees (~35 % LAI) were stem girdled within a 39 ha area, is testing the hypothesis that forest production will increase rather than decline with age, due to increases in nitrogen (N) availability, N allocation to the canopy, and the concurrent development of a more biologically and structurally complex canopy. Results thus far support our hypothesis that aging forests in the region may sustain high rates of C storage through shifts in N cycling and increased canopy complexity. Girdling-induced mortality of early successional species reduced soil respiration, accelerated fine root turnover, and prompted the redistribution of N from the foliage of early to later successional species. Nitrogen redistribution increased leaf area index (LAI) production by later successional species, offsetting declines in LAI from senescing early successional species. High rates of net primary production (NPP) were sustained in stands comprising a diverse assemblage of early and later successional species because later successional species, when already present in the canopy, rapidly compensated for declining growth of early successional species. Canopy structural complexity, which increased with forest age, was positively

  9. Relation between gastric emptying rate and energy intake in children compared with adults.

    PubMed

    Maes, B D; Ghoos, Y F; Geypens, B J; Hiele, M I; Rutgeerts, P J

    1995-02-01

    Measurement of gastric emptying rate of solids in children is difficult because the available methods are either invasive or induce a substantial radiation burden. In this study the newly developed 13C octanoic acid breath test was used to examine the gastric emptying rate of solids and milk in healthy children and to compare gastric emptying in children and adults. Fifteen healthy children and three groups of nine healthy adults were studied, using three different test meals labelled with 50 mg of 13C octanoic acid: a low caloric pancake (150 kcal), a high caloric pancake (250 kcal), and 210 ml of milk (134 kcal). Breath samples were taken before and at regular intervals after ingestion of the test meal, and analysed by isotope ratio mass spectrometry. The gastric emptying parameters were derived from the 13CO2 excretion curves by non-linear regression analysis. No significant difference was found between children and adults in the emptying rate of the low caloric solid test meal. In children as well as in adults, increasing the energy content of the solid meal resulted in a significantly slower emptying rate. The milk test meal, however, was emptied at a faster rate in adults and at slower rate in children compared with the low caloric solid test meal. Moreover, the emptying rate of milk in children was significantly slower than in adults. In conclusion, a similar gastric emptying rate of solids but a slower emptying of full cream milk was shown in children of school age compared with adults, using the non-radioactive 13C octanoic acid breath test. PMID:7883214

  10. Relation between gastric emptying rate and energy intake in children compared with adults.

    PubMed Central

    Maes, B D; Ghoos, Y F; Geypens, B J; Hiele, M I; Rutgeerts, P J

    1995-01-01

    Measurement of gastric emptying rate of solids in children is difficult because the available methods are either invasive or induce a substantial radiation burden. In this study the newly developed 13C octanoic acid breath test was used to examine the gastric emptying rate of solids and milk in healthy children and to compare gastric emptying in children and adults. Fifteen healthy children and three groups of nine healthy adults were studied, using three different test meals labelled with 50 mg of 13C octanoic acid: a low caloric pancake (150 kcal), a high caloric pancake (250 kcal), and 210 ml of milk (134 kcal). Breath samples were taken before and at regular intervals after ingestion of the test meal, and analysed by isotope ratio mass spectrometry. The gastric emptying parameters were derived from the 13CO2 excretion curves by non-linear regression analysis. No significant difference was found between children and adults in the emptying rate of the low caloric solid test meal. In children as well as in adults, increasing the energy content of the solid meal resulted in a significantly slower emptying rate. The milk test meal, however, was emptied at a faster rate in adults and at slower rate in children compared with the low caloric solid test meal. Moreover, the emptying rate of milk in children was significantly slower than in adults. In conclusion, a similar gastric emptying rate of solids but a slower emptying of full cream milk was shown in children of school age compared with adults, using the non-radioactive 13C octanoic acid breath test. PMID:7883214

  11. Consumers' Interest In Provider Ratings Grows, And Improved Report Cards And Other Steps Could Accelerate Their Use.

    PubMed

    Findlay, Steven D

    2016-04-01

    Encouraging patients and consumers to use data and other information in choosing health care providers is an important way to enhance patient engagement and improve the quality of care. The growing use of technology, including smart phones and near-ubiquitous Internet access, provides consumers with easy access to websites that collect and report assessments and ratings of providers, primarily physicians and hospitals. In addition to new technology, recent laws and changes in society and the delivery of care are laying the foundation for greater use by consumers of provider performance report cards. Such use could be accelerated if the shortcomings of current report card efforts were addressed. Recommendations include making online report cards easier to use and more understandable, engaging, substantive, and relevant to consumers' health and medical concerns and choices. PMID:27044970

  12. System modelling to support accelerated fuel transfer rate at EBR-II

    SciTech Connect

    Imel, G.R.; Houshyar, A.; Planchon, H.P.; Cutforth, D.C.

    1995-06-01

    The Experimental Breeder Reactor-II (EBR-II) ia a 62.5 MW(th) liquid metal reactor operated by Argonne National Laboratory for The United States Department of Energy. The reactor is located near Idaho Falls, Idaho at the Argonne-West site (ANL-W). Full power operation was achieved in 1964,- the reactor operated continuously since that time until October 1994 in a variety of configurations depending on the programmatic mission. A three year program was initiated in October, 1993 to replace the 330 depleted uranium blanket subassemblies (S/As) with stainless steel reflectors. It was intended to operate the reactor during the three year blanket unloading program, followed by about a half year of driver fuel unloading. However, in the summer of 1994, Congress dictacted that EBR-II be shut down October 1, and complete defueling without operation. To assist in the planning for resources needed for this defueling campaign, a mathematical model of the fuel handling sequence was developed utilizing the appropriate reliability factors and inherent mm constraints of each stage of the process. The model allows predictions of transfer rates under different scenarios. Additionally, it has facilitated planning of maintenance activities, as well as optimization of resources regarding manpower and modification effort. The model and its application is described in this paper.

  13. Metabolic rate measurements comparing supine with upright upper-body exercises

    NASA Technical Reports Server (NTRS)

    Fortney, Suzanne M.; Greenisen, Michael C.; Loftin, Karin C.; Beene, Donya; Freeman-Perez, Sondra; Hnatt, Linda

    1993-01-01

    The ground-based study that tested the hypothesis that metabolic rates during supine and upright upper-body exercises are similar (mean value of 200 kcal/h) is presented. Six subjects each performed supine or upright exercise at three exercise stations, a hand-cycle ergometer, a rope-pull device, and a torque wrench. After a baseline measurement of the metabolic rate at rest, the metabolic rate was measured twice at each exercise station. The mean metabolic rates (kcal/h) during supine (n = 6) and upright control (n = 4) exercise stations were not significantly different except for the rope-pull station, 153.5 +/- 16.6 (supine) as compared to 247.0 +/- 21.7 (upright), p is less than 0.05. This difference may be due in part to an increased mechanical efficiency of supine exercises (15.0 +/- 0.7 percent) as compared to that of upright exercises (11.0 +/- 1.08 percent), p is less than 0.05. The net energy input was significantly smaller for the supine rope-pull exercise (64 +/- 18) as compared to upright (176 +/- 20). The relationship between best-rest exercises, metabolic rates, and the incidence of decompression sickness (DCS) should be examined to determine the true risk of DCS in spaceflight extravehicular activities.

  14. Application of Overall Dynamic Body Acceleration as a Proxy for Estimating the Energy Expenditure of Grazing Farm Animals: Relationship with Heart Rate

    PubMed Central

    Miwa, Masafumi; Oishi, Kazato; Nakagawa, Yasuhiro; Maeno, Hiromichi; Anzai, Hiroki; Kumagai, Hajime; Okano, Kanji; Tobioka, Hisaya; Hirooka, Hiroyuki

    2015-01-01

    Estimating the energy expenditure of farm animals at pasture is important for efficient animal management. In recent years, an alternative technique for estimating energy expenditure by measuring body acceleration has been widely performed in wildlife and human studies, but the availability of the technique in farm animals has not yet been examined. In the present study, we tested the potential use of an acceleration index, overall dynamic body acceleration (ODBA), as a new proxy for estimating the energy expenditure of grazing farm animals (cattle, goats and sheep) at pasture with the simultaneous evaluation of a conventional proxy, heart rate. Body accelerations in three axes and heart rate for cows (n = 8, two breeds), goats (n = 6) and sheep (n = 5) were recorded, and the effect of ODBA calculated from the body accelerations on heart rate was analyzed. In addition, the effects of the two other activity indices, the number of steps and vectorial dynamic body acceleration (VeDBA), on heart rate were also investigated. The results of the comparison among three activity indices indicated that ODBA was the best predictor for heart rate. Although the relationship between ODBA and heart rate was different between the groups of species and breeds and between individuals (P<0.01), the difference could be explained by different body weights; a common equation could be established by correcting the body weights (M: kg): heart rate (beats/min) = 147.263∙M-0.141 + 889.640∙M-0.179∙ODBA (g). Combining this equation with the previously reported energy expenditure per heartbeat, we estimated the energy expenditure of the tested animals, and the results indicated that ODBA is a good proxy for estimating the energy expenditure of grazing farm animals across species and breeds. The utility and simplicity of the procedure with acceleration loggers could make the accelerometry technique a worthwhile option in field research and commercial farm use. PMID:26030931

  15. Comparative Cryopreservation of Avian Spermatozoa: Effects of Cooling and Thawing Rates on Sperm Viability and Fertility

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A comparative approach (Sandhill crane (Grus canadensis, n = 13); domestic white turkey (Meleagridis gallopavo n = 40) was used to determine the possible benefits of the addition of different compounds and variation in cooling and thawing rates, and volume of semen. Sperm was frozen in cryovials usi...

  16. Comparative genomics reveals convergent rates of evolution in ant-plant mutualisms.

    PubMed

    Rubin, Benjamin E R; Moreau, Corrie S

    2016-01-01

    Symbiosis-the close and often long-term interaction of species-is predicted to drive genome evolution in a variety of ways. For example, parasitic interactions have been shown to increase rates of molecular evolution, a trend generally attributed to the Red Queen Hypothesis. However, it is much less clear how mutualisms impact the genome, as both increased and reduced rates of change have been predicted. Here we sequence the genomes of seven species of ants, three that have convergently evolved obligate plant-ant mutualism and four closely related species of non-mutualists. Comparing these sequences, we investigate how genome evolution is shaped by mutualistic behaviour. We find that rates of molecular evolution are higher in the mutualists genome wide, a characteristic apparently not the result of demography. Our results suggest that the intimate relationships of obligate mutualists may lead to selective pressures similar to those seen in parasites, thereby increasing rates of evolution. PMID:27557866

  17. Comparative genomics reveals convergent rates of evolution in ant–plant mutualisms

    PubMed Central

    Rubin, Benjamin E. R.; Moreau, Corrie S.

    2016-01-01

    Symbiosis—the close and often long-term interaction of species—is predicted to drive genome evolution in a variety of ways. For example, parasitic interactions have been shown to increase rates of molecular evolution, a trend generally attributed to the Red Queen Hypothesis. However, it is much less clear how mutualisms impact the genome, as both increased and reduced rates of change have been predicted. Here we sequence the genomes of seven species of ants, three that have convergently evolved obligate plant–ant mutualism and four closely related species of non-mutualists. Comparing these sequences, we investigate how genome evolution is shaped by mutualistic behaviour. We find that rates of molecular evolution are higher in the mutualists genome wide, a characteristic apparently not the result of demography. Our results suggest that the intimate relationships of obligate mutualists may lead to selective pressures similar to those seen in parasites, thereby increasing rates of evolution. PMID:27557866

  18. Platelet-Rich Fibrin Promotes an Accelerated Healing of Achilles Tendon When Compared to Platelet-Rich Plasma in Rat

    PubMed Central

    Dietrich, Franciele; L. Duré, Gustavo; P. Klein, Caroline; F. Bampi, Vinícius; V. Padoin, Alexandre; D. Silva, Vinícius; Braga-Silva, Jefferson

    2015-01-01

    BACKGROUND Autologous platelet concentrate has been used to improve the function and regeneration of injured tissues. Tendinopathies are common in clinical practice, although long-term treatment is required. On the basis of lead time, we compared the effect of using platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) in repairing rat Achilles tendon. METHODS The effectiveness of using PRP and PRF was evaluated after 14 and 28 postoperative days by histological analysis. The quantification of collagen types I and III was performed by Sirius red staining. Qualitatively, the data were verified with hematoxylin-eosin (H&E) staining. RESULTS In Sirius red staining, no significant treatment differences were found between groups. Statistical difference was observed only between PRP (37.2% collagen) and the control group (16.2%) 14 days after treatment. Intra-groups compared twice showed a difference for collagen I (27.8% and 47.7%) and III (66.9% and 46.0%) in the PRF group. The control group showed differences only in collagen I (14.2% and 40.9%) and no other finding was observed in the PRP group. In H&E staining, PRF showed a better cellular organization when compared to the other groups at 28 days. CONCLUSION Our study suggests that PRF promotes accelerated regeneration of the Achilles tendon in rats, offering promising prospects for future clinical use. PMID:26284178

  19. Dual-rate-loop control based on disturbance observer of angular acceleration for a three-axis aerial inertially stabilized platform.

    PubMed

    Zhou, Xiangyang; Jia, Yuan; Zhao, Qiang; Cai, Tongtong

    2016-07-01

    This paper presents a dual-rate-loop control method based on disturbance observer (DOB) of angular acceleration for a three-axis ISP for aerial remote sensing applications, by which the control accuracy and stabilization of ISP are improved obviously. In stabilization loop of ISP, a dual-rate-loop strategy is designed through constituting inner rate loop and the outer rate loop, by which the capability of disturbance rejection is advanced. Further, a DOB-based on angular acceleration is proposed to attenuate the influences of the main disturbances on stabilization accuracy. Particularly, an information fusion method is suggested to obtain accurate angular acceleration in DOB design, which is the key for the disturbance compensation. The proposed methods are theoretically analyzed and experimentally validated to illustrate the effectiveness. PMID:27016450

  20. Comparing a volume based template approach and ultrasound guided freehand approach in multicatheter interstitial accelerated partial breast irradiation

    PubMed Central

    Koh, Vicky Y.; Buhari, Shaik A.; Tan, Poh Wee; Tan, Yun Inn; Leong, Yuh Fun; Earnest, Arul

    2014-01-01

    Purpose Currently, there are two described methods of catheter insertion for women undergoing multicatheter interstitial accelerated partial breast irradiation (APBI). These are a volume based template approach (template) and a non-template ultrasound guidance freehand approach (non-template). We aim to compare dosimetric endpoints between the template and non-template approach. Material and methods Twenty patients, who received adjuvant multicatheter interstitial APBI between August 2008 to March 2010 formed the study cohort. Dosimetric planning was based on the RTOG 04-13 protocol. For standardization, the planning target volume evaluation (PTV-Eval) and organs at risk were contoured with the assistance of the attending surgeon. Dosimetric endpoints include D90 of the PTV-Eval, Dose Homogeneity Index (DHI), V200, maximum skin dose (MSD), and maximum chest wall dose (MCD). A median of 18 catheters was used per patient. The dose prescribed was 34 Gy in 10 fractions BID over 5 days. Results The average breast volume was 846 cm3 (526-1384) for the entire cohort and there was no difference between the two groups (p = 0.6). Insertion time was significantly longer for the non-template approach (mean 150 minutes) compared to the template approach (mean: 90 minutes) (p = 0.02). The planning time was also significantly longer for the non-template approach (mean: 240 minutes) compared to the template approach (mean: 150 minutes) (p < 0.01). The template approach yielded a higher D90 (mean: 95%) compared to the non-template approach (mean: 92%) (p < 0.01). There were no differences in DHI (p = 0.14), V200 (p = 0.21), MSD (p = 0.7), and MCD (p = 0.8). Conclusions Compared to the non-template approach, the template approach offered significant shorter insertion and planning times with significantly improved dosimetric PTV-Eval coverage without significantly compromising organs at risk dosimetrically. PMID:25097558

  1. Stability and chaotic dynamics of a rate gyro with feedback control under uncertain vehicle spin and acceleration

    NASA Astrophysics Data System (ADS)

    Chen, Heng-Hui

    2004-06-01

    An analysis of stability and chaotic dynamics is presented by a single-axis rate gyro subjected to linear feedback control loops. This rate gyro is supposed to be mounted on a space vehicle which undergoes an uncertain angular velocity ωZ( t) around its spin axis. And simultaneously acceleration ω˙X(t) occurs with respect to the output axis. The necessary and sufficient conditions of stability for the autonomous case, whose vehicle undergoes a steady rotation, were provided by Routh-Hurwitz theory. Also, the degeneracy conditions of the non-hyperbolic point were derived and the dynamics of the resulting system on the center manifold near the double-zero degenerate point by using center manifold and normal form methods were examined. The stability of the non-linear non-autonomous system was investigated by Liapunov stability and instability theorems. As the electrical time constant is much smaller than the mechanical time constant, the singularly perturbed system can be obtained by the singular perturbation theory. The Liapunov stability of this system by studying the reduced and boundary-layer systems was also analyzed. Numerical simulations were performed to verify the analytical results. The stable regions of the autonomous system were obtained in parametric diagrams. For the non-autonomous case in which ωZ( t) oscillates near boundary of stability, periodic, quasiperiodic and chaotic motions were demonstrated by using time history, phase plane and Poincaré maps.

  2. Long-term Cosmetic Outcomes and Toxicities of Proton Beam Therapy Compared With Photon-Based 3-Dimensional Conformal Accelerated Partial-Breast Irradiation: A Phase 1 Trial

    SciTech Connect

    Galland-Girodet, Sigolène; Pashtan, Itai; MacDonald, Shannon M.; Ancukiewicz, Marek; Hirsch, Ariel E.; Kachnic, Lisa A.; Specht, Michelle; Gadd, Michele; Smith, Barbara L.; Powell, Simon N.; Recht, Abram; Taghian, Alphonse G.

    2014-11-01

    Purpose: To present long-term outcomes of a prospective feasibility trial using either protons or 3-dimensional conformal photon-based (accelerated partial-breast irradiation [APBI]) techniques. Methods and Materials: From October 2003 to April 2006, 98 evaluable patients with stage I breast cancer were treated with APBI (32 Gy in 8 fractions given twice daily) on a prospective clinical trial: 19 with proton beam therapy (PBT) and 79 with photons or mixed photons/electrons. Median follow-up was 82.5 months (range, 2-104 months). Toxicity and patient satisfaction evaluations were performed at each visit. Results: At 7 years, the physician rating of overall cosmesis was good or excellent for 62% of PBT patients, compared with 94% for photon patients (P=.03). Skin toxicities were more common for the PBT group: telangiectasia, 69% and 16% (P=.0013); pigmentation changes, 54% and 22% (P=.02); and other late skin toxicities, 62% and 18% (P=.029) for PBT and photons, respectively. There were no significant differences between the groups in the incidences of breast pain, edema, fibrosis, fat necrosis, skin desquamation, and rib pain or fracture. Patient-reported cosmetic outcomes at 7 years were good or excellent for 92% and 96% of PBT and photon patients, respectively (P=.95). Overall patient satisfaction was 93% for the entire cohort. The 7-year local failure rate for all patients was 6%, with 3 local recurrences in the PBT group (7-year rate, 11%) and 2 in photon-treated patients (4%) (P=.22). Conclusions: Local failure rates of 3-dimensional APBI and PBT were similar in this study. However, PBT, as delivered in this study, led to higher rates of long-term telangiectasia, skin color changes, and skin toxicities. We recommend the use of multiple fields and treatment of all fields per treatment session or the use of scanning techniques to minimize skin toxicity.

  3. Comparative rates of wind versus water erosion from a small semiarid watershed in southern Arizona, USA

    NASA Astrophysics Data System (ADS)

    Zhang, Y.-G.; Nearing, M. A.; Liu, B. Y.; Van Pelt, R. S.; Stone, J. J.; Wei, H.; Scott, R. L.

    2011-11-01

    The relative erosion rates of wind and water erosion have rarely been studied simultaneously and are poorly quantified. In this study, wind and water erosion rates were simultaneously measured and compared over 2 yrs for a small rangeland watershed in the Santa Rita Experimental Range in southern Arizona. Average horizontal, wind-driven sediment flux was 7.0 g m -1 d -1 during the study period. The combined soil erosion rate by water and wind was 7.60 t ha -1 yr -1, with only 0.08 t ha -1 yr -1 attributed to wind during the 2 yrs. The results of this study showed that rates of soil erosion by water greatly exceeded rates of erosion by wind during the study period in this small watershed. Comparison between these results and other recent studies in the same area suggest that measurements of horizontal sediment fluxes by wind and water are not necessarily indicative of relative net soil erosion rates on a unit area basis because the measurements of the wind flux sediment cannot be considered as mass of soil loss per unit area per unit time.

  4. Robotic CABG decreases 30-day complication rate, length of stay and acute care facility discharge rate compared to conventional surgery

    PubMed Central

    Leyvi, Galina; Forest, Stephen; Srinivas, V. S.; Greenberg, Mark; Wang, Nan; Mais, Alec; Snyder, Max; DeRose, Joseph J.

    2015-01-01

    Summary Objective The objective of this study was to compare the short term outcomes of robotic with conventional on pump coronary artery bypass grafting (CABG). Methods The study population included 2091 consecutive patients who underwent either conventional or robotic CABG from January 2007 to March 2012. Pre-operative, intra-operative and 30-day post-operative variables were collected for each group. In order to compare the incidence of rapid recovery between conventional and robotic CABG, the surrogate variables of early discharge and discharge to home (versus rehabilitation or acute care facility) were evaluated. A multivariate logistic regression analysis was utilized. Results One hundred and fifty robotic and 1,619 conventional CABG cases were analyzed. Multivariate logistic regression analysis demonstrated that robotic surgery was a strong predictor of lower 30-day complications (OR = 0.24, p=0.005), short length of stay (OR 3.31, p < 0.001), and decreased need for an acute care facility (OR 0.55, p = 0.032). In the presence of complications (NY State Complication Composite), the robotic technique was not associated with a change in discharge status. Conclusions In this retrospective review robotic CABG was associated with a lower 30-day complication rate, a shorter length of stay and a lower incidence of acute care facility discharge than conventional on pump CABG. It may suggest a more rapid recovery to pre-operative status after robotic surgery: however, only a randomized prospective study could confirm the advantages of a robotic approach PMID:25238421

  5. Sensor response rate accelerator

    DOEpatents

    Vogt, Michael C.

    2002-01-01

    An apparatus and method for sensor signal prediction and for improving sensor signal response time, is disclosed. An adaptive filter or an artificial neural network is utilized to provide predictive sensor signal output and is further used to reduce sensor response time delay.

  6. N-15 NMR Spectroscopy as a Method for Comparing the Rates of Imidization of Several Diamines

    NASA Technical Reports Server (NTRS)

    Johnson, J. Christopher; Kuczmarski, Maria A.

    2006-01-01

    The relative rates of the conversion of amide-acid to imide was measured for a series or aromatic diamines that have been identified as potential replacements for 4,4'-methylene dianiline (MDA) in high-temperature polyimides and polymer composites. These rates were compared with the N-15 NMR resonances of the unreacted amines. The initial rates of imidization track with the difference in chemical shift between the amine nitrogens in MDA and those in the subject diamines. This comparison demonstrated that N-15 NMR spectroscopy is appropriate for the rapid screening of candidate diamines to determine their reactivity relative to MDA, and can serve to provide guidance to the process of creating the time-temperature profiles used in processing these materials into polymer matrix composites.

  7. Rate of British psychiatric combat casualties compared to recent American wars.

    PubMed

    Price, H H

    2007-01-01

    This paper examines factors leading to the low rate of combat psychiatric casualties in the British recapture of the Falklands compared to the American experience in North Africa, Italy, Europe and South Pacific theatres during World War II, the Korean Conflict and Vietnam. The factors compared are those thought to affect rates seen in these past wars. The factors highlighted are psychiatric screening of evacuees, presence of psychiatric personnel in line units, intensity of combat and use of elite units. Factors also mentioned are presence of possible occult psychiatric casualties such as frostbite and malaria, amount of indirect fire and the offensive or defensive nature of the combat. A unique aspect of the Falklands War examined is the exclusive use of hospital ships to treat psychiatric casualties and the impact of the Geneva Convention rules regarding hospital ships on the classic treatment principles of proximity and expectancy. The types and numbers of various diagnoses are also presented. The British Campaign in the Falklands produced a remarkably low rate of psychiatric casualties. When viewed in light of American experience in recent wars, this low rate represents a concentration of optimal factors leading to healthy function in combat. The results of this war should not be used to predict a similar outcome in future combat as this particular constellation of factors may not recur. PMID:18214088

  8. Evaluation of different indirect measures of rate of drug absorption in comparative pharmacokinetic studies.

    PubMed

    Lacey, L F; Keene, O N; Duquesnoy, C; Bye, A

    1994-02-01

    As indirect measures of rate of drug absorption (metrics), maximum plasma concentration (Cmax) is confounded by extent of drug absorption and the time to reach Cmax (tmax) is a discrete variable, dependent on blood sampling frequency. Building on the work of Endrenyi et al., we have compared different metrics, including Cmax/area under the curve of concentration versus time from time zero to infinity (AUC infinity), partial AUC from zero to tmax (AUCp), and Cmax.tmax with simulated experiments. Importantly, the performance of these metrics was assessed with the results of actual pharmacokinetic studies involving Glaxo drugs. The results of the simulated and real experiments were consistent and produced the following unambiguous findings: (1) Cmax/AUC infinity is a more powerful metric than Cmax in establishing bioequivalence when the formulations are truly bioequivalent; (2) Cmax/AUC infinity is more sensitive than Cmax at detecting differences in rate of absorption when they exist; and (3) the treatment ratios for AUCp, AUCp/AUC infinity, and Cmax.tmax are very imprecisely estimated and are of no practical value as measures of rate of absorption. Of the metrics examined, Cmax/AUC infinity is the most sensitive and powerful indirect measure of rate of drug absorption in comparative pharmacokinetic studies involving immediate-release dosage forms and should be used instead of Cmax in bioequivalence testing. PMID:8169791

  9. Antioxidant capacity of individual and combined virgin olive oil minor compounds evaluated at mild temperature (25 and 40°C) as compared to accelerated and antiradical assays.

    PubMed

    Mancebo-Campos, Vanessa; Salvador, María Desamparados; Fregapane, Giuseppe

    2014-05-01

    The individual and combined antioxidant and antiradical capacity of the main minor compounds of virgin olive oil (α-tocopherol, hydroxytyrosol, tyrosol and oleuropein aglycone) spiked in Purified Olive Oil (POO) as the lipid matrix model is described. The antioxidant activity was assessed under mild temperature conditions (25 and 40°C) to mimic the autoxidation process during real storage conditions. These results were compared with accelerated (Rancimat Induction Period) and antiradical (DPPH) tests. The higher concentration of o-diphenols (hydroxytyrosol or oleuropein aglycone) in olive oil led to a lower oxidation rate under the conditions studied, resulting in a strong antioxidant effect. Remarkably α-tocopherol acted as a pro-oxidant at 25 and 40°C, in particular during the first oxidation stage. In contrast, this compound behaved as an antioxidant under Rancimat and DPPH conditions. The oxidation rate constant as a function of the concentration of spiked compound fit an exponential decay model very well and therefore the progress of the oxidation reaction could be predicted. No synergistic or antagonistic effects were generally observed when combined antioxidant compounds were assayed. PMID:24360465

  10. Are Interpersonal Violence Rates Higher Among Young Women in College Compared With Those Never Attending College?

    PubMed

    Coker, Ann L; Follingstad, Diane R; Bush, Heather M; Fisher, Bonnie S

    2016-05-01

    Estimates of sexual violence and partner violence rates among young women are generated primarily from college samples. Few studies have data to compare rates among similar-aged women attending college with those who never attended college. This study aims to estimate rates of partner violence by type (sexual, physical, and psychological) and severity (mild, moderate, severe), sexual harassment, and knowing or suspecting that someone put a drug in a drink (drugged drink) among a national sample of 959 young women aged 18 to 24 in an intimate relationship in the past 12 months who were either currently in college (college;n= 272) or never attended college (non-college;n= 687). After adjusting for demographic differences between these two groups, no significant differences were found in rates of sexual partner violence (28.4% non-college, 23.5% college), physical partner violence (27.9% non-college, 26.3% college), psychological partner violence (Mscore: 6.10 non-college, 5.59 college), sexual harassment (15.5% non-college, 14.1% college), or drugged drink (8.5% non-college, 7.8% college). Finding high rates of interpersonal violence among young women who are and are not currently attending college indicates the need to target all young adults with violence prevention interventions in educational, workplace, and other community-based settings. PMID:25604971

  11. Comparative Study of Radiation Dosage Distribution and Medical Implication of Quasi-monoenergetic Proton Generated from Laser Acceleration of Ultra-thin Foil

    NASA Astrophysics Data System (ADS)

    Batpurev, Temuge; Cao, Jennifer; Xie, Wang; Liu, Tung-Chang; Shao, Xi; Liu, Chuan-Sheng

    2012-10-01

    Recently the search for mono-energetic protons has gained great interest, particularly in applications such as proton therapy for cancer treatment. The advantage of proton therapy is that unlike photon radiation, proton beams deposit most of the energy at the tumor, sparing surrounding tissue and vital organs. A compact laser-driven proton accelerator is attractive for proton cancer therapy since the electric fields for particle acceleration can reach the order of tens of GV per cm which allows large reduction of the system size. Recent work by Liu et al. [2012] shows that laser acceleration of an ultra-thin multi-ion foil can generate high quality quasi-monoenergetic proton beams. The proton acceleration is due to the combination of radiation pressure and heavy-ion Coulomb repulsion. To assess the feasibility of laser-proton cancer therapy with such a proton accelerator, we simulated the interaction of protons with water and determine the radiation dosage deposition for particle beams produced from the PIC simulation of laser acceleration of multi-ion targets. We used the SRIM code to calculate the depth and lateral dose distribution of protons. We also compared the dosage map produced from protons generated from laser acceleration of single ion and multi-ion targets.

  12. Comparative transcriptome and metabolome provides new insights into the regulatory mechanisms of accelerated senescence in litchi fruit after cold storage.

    PubMed

    Yun, Ze; Qu, Hongxia; Wang, Hui; Zhu, Feng; Zhang, Zhengke; Duan, Xuewu; Yang, Bao; Cheng, Yunjiang; Jiang, Yueming

    2016-01-01

    Litchi is a non-climacteric subtropical fruit of high commercial value. The shelf life of litchi fruit under ambient conditions (AC) is approximately 4-6 days. Post-harvest cold storage prolongs the life of litchi fruit for up to 30 days with few changes in pericarp browning and total soluble solids. However, the shelf life of litchi fruits at ambient temperatures after pre-cold storage (PCS) is only 1-2 days. To better understand the mechanisms involved in the rapid fruit senescence induced by pre-cold storage, a transcriptome of litchi pericarp was constructed to assemble the reference genes, followed by comparative transcriptomic and metabolomic analyses. Results suggested that the senescence of harvested litchi fruit was likely to be an oxidative process initiated by ABA, including oxidation of lipids, polyphenols and anthocyanins. After cold storage, PCS fruit exhibited energy deficiency, and respiratory burst was elicited through aerobic and anaerobic respiration, which was regulated specifically by an up-regulated calcium signal, G-protein-coupled receptor signalling pathway and small GTPase-mediated signal transduction. The respiratory burst was largely associated with increased production of reactive oxygen species, up-regulated peroxidase activity and initiation of the lipoxygenase pathway, which were closely related to the accelerated senescence of PCS fruit. PMID:26763309

  13. Comparative transcriptome and metabolome provides new insights into the regulatory mechanisms of accelerated senescence in litchi fruit after cold storage

    PubMed Central

    Yun, Ze; Qu, Hongxia; Wang, Hui; Zhu, Feng; Zhang, Zhengke; Duan, Xuewu; Yang, Bao; Cheng, Yunjiang; Jiang, Yueming

    2016-01-01

    Litchi is a non-climacteric subtropical fruit of high commercial value. The shelf life of litchi fruit under ambient conditions (AC) is approximately 4–6 days. Post-harvest cold storage prolongs the life of litchi fruit for up to 30 days with few changes in pericarp browning and total soluble solids. However, the shelf life of litchi fruits at ambient temperatures after pre-cold storage (PCS) is only 1–2 days. To better understand the mechanisms involved in the rapid fruit senescence induced by pre-cold storage, a transcriptome of litchi pericarp was constructed to assemble the reference genes, followed by comparative transcriptomic and metabolomic analyses. Results suggested that the senescence of harvested litchi fruit was likely to be an oxidative process initiated by ABA, including oxidation of lipids, polyphenols and anthocyanins. After cold storage, PCS fruit exhibited energy deficiency, and respiratory burst was elicited through aerobic and anaerobic respiration, which was regulated specifically by an up-regulated calcium signal, G-protein-coupled receptor signalling pathway and small GTPase-mediated signal transduction. The respiratory burst was largely associated with increased production of reactive oxygen species, up-regulated peroxidase activity and initiation of the lipoxygenase pathway, which were closely related to the accelerated senescence of PCS fruit. PMID:26763309

  14. Comparing Background and Recent Erosion Rates in Degraded Areas of Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Fernandes, N.; Bierman, P. R.; Sosa-Gonzalez, V.; Rood, D. H.; Fontes, R. L.; Santos, A. C.; Godoy, J. M.; Bhering, S.

    2014-12-01

    Soil erosion is a major problem in northwestern Rio de Janeiro State where, during the last three centuries, major land-use changes took place, associated with the replacement of the original rainforest by agriculture and grazing. The combination of steep hillslopes, erodible soils, sparse vegetation, natural and human-induced fires, as well as downslope ploughing, led to an increase in surface runoff and surface erosion on soil-mantled hillslopes; together, these actions and responses caused a decline in soil productivity. In order to estimate changes in erosion rates over time, we compared erosion rates measured at different spatial and temporal scales, both background (natural) and short-term (human-induced during last few decades). Background long-term erosion rates were measured using in-situ produced cosmogenic 10Be in the sand fraction quartz of active river channel sediment in four basins in the northwestern portion of Rio de Janeiro State. In these basins, average annual precipitation varies from 1,200 to 1,300 mm, while drainage areas vary from 15 to 7,200 km2. Short-term erosion rates were measured in one of these basins from fallout 210Pb in soil samples collected along a hillslope transect located in an abandoned agriculture field. In this transect, 190 undisturbed soil samples (three replicates) were collected from the surface to 0.50 m depth (5 cm vertical intervals) in six soil pits. 10Be average background, basin-wide, erosion rates in the area are ~ 13 m/My; over the last decades, time-integrated (210Pb) average hillslope erosion rates are around 1450 m/Myr, with maximum values at the steepest portion of convex hillslopes of about 2000 m/Myr. These results suggest that recent hillslope erosion rates are about 2 orders of magnitude above background rates of sediment generation integrated over many millennia. This unsustainable rate of soil loss has severely decreased soil productivity eventually leading to the abandonment of farming activities in

  15. ACCELERATED SITE TECHNOLOGY DEPLOYMENT COST AND PERFORMANCE REPORT COMPARABILITY OF ISOCS INSTRUMENT IN RADIONUCLIDE CHARACTERICATION AT BROOKHAVEN NATIONAL LABORATORY

    SciTech Connect

    KALB,P.; LUCKETT,L.; MILLER,K.; GOGOLAK,C.; MILIAN,L.

    2001-03-01

    This report describes a DOE Accelerated Site Technology Deployment project being conducted at Brookhaven National Laboratory to deploy innovative, radiological, in situ analytical techniques. The technologies are being deployed in support of efforts to characterize the Brookhaven Graphite Research Reactor (BGRR) facility, which is currently undergoing decontamination and decommissioning. This report focuses on the deployment of the Canberra Industries In Situ Object Counting System (ISOCS) and assesses its data comparability to baseline methods of sampling and laboratory analysis. The battery-operated, field deployable gamma spectrometer provides traditional spectra of counts as a function of gamma energy. The spectra are then converted to radionuclide concentration by applying innovative efficiency calculations using monte carlo statistical methods and pre-defined geometry templates in the analysis software. Measurement of gamma emitting radionuclides has been accomplished during characterization of several BGRR components including the Pile Fan Sump, Above Ground Ducts, contaminated cooling fans, and graphite pile internals. Cs-137 is the predominant gamma-emitting radionuclide identified, with smaller quantities of Co-60 and Am-241 detected. The Project used the Multi-Agency Radiation Survey and Site Investigation Manual guidance and the Data Quality Objectives process to provide direction for survey planning and data quality assessment. Analytical results have been used to calculate data quality indicators (DQI) for the ISOCS measurements. Among the DQIs assessed in the report are sensitivity, accuracy, precision, bias, and minimum detectable concentration. The assessment of the in situ data quality using the DQIs demonstrates that the ISOCS data quality can be comparable to definitive level laboratory analysis when the field instrument is supported by an appropriate Quality Assurance Project Plan. A discussion of the results obtained by ISOCS analysis of

  16. Measuring Disability: Comparing the Impact of Two Data Collection Approaches on Disability Rates

    PubMed Central

    Sabariego, Carla; Oberhauser, Cornelia; Posarac, Aleksandra; Bickenbach, Jerome; Kostanjsek, Nenad; Chatterji, Somnath; Officer, Alana; Coenen, Michaela; Chhan, Lay; Cieza, Alarcos

    2015-01-01

    The usual approach in disability surveys is to screen persons with disability upfront and then ask questions about everyday problems. The objectives of this paper are to demonstrate the impact of screeners on disability rates, to challenge the usual exclusion of persons with mild and moderate disability from disability surveys and to demonstrate the advantage of using an a posteriori cut-off. Using data of a pilot study of the WHO Model Disability Survey (MDS) in Cambodia and the polytomous Rasch model, metric scales of disability were built. The conventional screener approach based on the short disability module of the Washington City Group and the a posteriori cut-off method described in the World Disability Report were compared regarding disability rates. The screener led to imprecise rates and classified persons with mild to moderate disability as non-disabled, although these respondents already experienced important problems in daily life. The a posteriori cut-off applied to the general population sample led to a more precise disability rate and allowed for a differentiation of the performance and needs of persons with mild, moderate and severe disability. This approach can be therefore considered as an inclusive approach suitable to monitor the Convention on the Rights of Persons with Disabilities. PMID:26308039

  17. Measuring Disability: Comparing the Impact of Two Data Collection Approaches on Disability Rates.

    PubMed

    Sabariego, Carla; Oberhauser, Cornelia; Posarac, Aleksandra; Bickenbach, Jerome; Kostanjsek, Nenad; Chatterji, Somnath; Officer, Alana; Coenen, Michaela; Chhan, Lay; Cieza, Alarcos

    2015-09-01

    The usual approach in disability surveys is to screen persons with disability upfront and then ask questions about everyday problems. The objectives of this paper are to demonstrate the impact of screeners on disability rates, to challenge the usual exclusion of persons with mild and moderate disability from disability surveys and to demonstrate the advantage of using an a posteriori cut-off. Using data of a pilot study of the WHO Model Disability Survey (MDS) in Cambodia and the polytomous Rasch model, metric scales of disability were built. The conventional screener approach based on the short disability module of the Washington City Group and the a posteriori cut-off method described in the World Disability Report were compared regarding disability rates. The screener led to imprecise rates and classified persons with mild to moderate disability as non-disabled, although these respondents already experienced important problems in daily life. The a posteriori cut-off applied to the general population sample led to a more precise disability rate and allowed for a differentiation of the performance and needs of persons with mild, moderate and severe disability. This approach can be therefore considered as an inclusive approach suitable to monitor the Convention on the Rights of Persons with Disabilities. PMID:26308039

  18. Apparent I-Xe Cooling Rates of Chondrules Compared with Silicates from the Colomera Iron Meteorite

    NASA Technical Reports Server (NTRS)

    Hohenberg, C. M.; Meshik, A. P.; Pravdivseva, O. V.

    2004-01-01

    In I-Xe dating, a regular pattern of increasing Xe-129/128Xe-128 ratio with increasing extraction temperature is often observed. If one makes the crude assumption that the temperatures at which the Xe is extracted in the laboratory is approximately the same as the temperature at which those sites closed 4.6 Ga ago, a (zeroth order) model cooling rate can be found. In order to test and refine this model we can apply the cooling theory of Dodson to those extraction steps approaching the I-Xe isochrons. Using an Arrhenius plot for these temperature fractions, and assuming that an only single phase is involved, the effective diffusion parameters can be estimated (frequency factor and activation energy). From the apparent (zeroth order) cooling rate, the closure temperature can be estimated from the Dodson equation. This model closure temperature can then be compared with the actual laboratory temperature at which the isochron begins. The ratio of the closure temperature and the temperature corresponding to the start of the isochron provides the ratio of the two temperature scales, incorporation and extraction. The actual cooling rate is then given by the apparent (zeroth order) cooling rate times the temperature scale factor. Figure 1 shows Arrhenius plots for I-Xe data

  19. A Comparative Study of Fibroid Ablation Rates Using Radio Frequency or High-Intensity Focused Ultrasound

    SciTech Connect

    Meng Xin; He Guangbin; Zhang Jun; Han Zenghui; Yu Ming; Zhang Miaomiao; Tang Yu; Fang Ling; Zhou Xiaodong

    2010-08-15

    This study compared the technical success of fibroid devascularization using high-intensity focused ultrasound (HIFU) and radio frequency (RF) to provide an experimental basis for the clinical selection of a suitable, minimally invasive method for treating uterine fibroids. Patients were randomly divided into two groups and treated with HIFU or RF accordingly. The two groups of patients were divided again into subgroups A, B, and C based on fibroid diameter and subgroups A', B', and C' based on fibroid blood supply grades. The fibroid diameters in subgroups A, B, and C were 2.0 cm {<=} D < 4.0 cm, 4.0 cm {<=} D<6.0 cm and 6.0 cm {<=} D<8.0 cm, respectively, and fibroid blood supplies were classified into three grades corresponding to subgroups A', B', and C', respectively. The complete ablation rates of the two treatments were compared by contrast-enhanced ultrasound. Both treatments were effective, but the general complete ablation rate of RF was higher than that of HIFU (p < 0.05). The comparison between the two treatments in subgroup A and subgroup A' showed that the complete ablation rate of HIFU was as good as that of RF (p > 0.05). In other subgroups, the complete ablation rates of RF were better than those of HIFU (p < 0.05). No severe complications were observed after these two treatments. RF can be applied for the majority of fibroids. As a noninvasive therapy, HIFU could be the preferred method for the treatment of small, hypovascular fibroids.

  20. A Pilot Study Comparing Hospital Readmission Rates In Patients Receiving Rivaroxaban or Enoxaparin After Orthopedic Surgery

    PubMed Central

    Herschman, Melissa A.; Rigelsky, Frank S.; Axtell, Sandra S.

    2016-01-01

    Purpose: A pilot study was conducted to determine whether rivaroxaban (Xarelto, Janssen Pharmaceuticals) resulted in a lower 30-day all-cause readmission rate compared with enoxaparin (Lovenox, Sanofi-Aventis) after total hip arthroplasty (THA) or total knee arthroplasty (TKA) at a community hospital. Methods: The study was a single-center, retrospective, chart-review investigation involving patients who underwent THA or TKA between May 2013 and May 2014. The study’s primary endpoint was the 30-day all-cause readmission rate. The 30-day readmission rate due to venous thromboembolism (VTE) or any bleeding event was a secondary endpoint. Patients who received oral rivaroxaban (10 mg once daily) or subcutaneous enoxaparin (30 mg twice daily or 40 mg once daily) were included in the study. Patients were excluded if they had a history of heparin-induced thrombocytopenia; a history of allergy associated with heparin or rivaroxaban; a hypercoagulation disorder; or creatinine clearance of less than 30 mL/min. Patients were also excluded if they had received an anticoagulant before admission, were discharged more than 30 days after admission, or died before discharge. Results: A total of 543 patients underwent THA or TKA between May 2013 and May 2014. We reviewed 405 patient charts, and 240 patients met the inclusion criteria. Most of the excluded patients had received only aspirin for VTE prophylaxis. The primary outcome was reached in eight of 213 patients in the rivaroxaban group (3.76%) and in one of 27 patients in the enoxaparin group (3.70%) (P = 1). The secondary outcome was reached in two patients (0.9%) in the rivaroxaban group. Conclusion: Rivaroxaban did not significantly reduce the 30-day all-cause readmission rate compared with enoxaparin in patients who had undergone THA or TKA. Further research in a larger, multicenter study is needed to confirm these results. PMID:27313435

  1. Development and Initial Validation of the Student Rating of Environmental Stressors Scale: Stressors Faced by Students in Accelerated High School Curricula

    ERIC Educational Resources Information Center

    Suldo, Shannon M.; Dedrick, Robert F.; Shaunessy-Dedrick, Elizabeth; Roth, Rachel A.; Ferron, John

    2015-01-01

    High school students in accelerated curricula face stressors beyond typical adolescent developmental challenges. The Student Rating of Environmental Stressors Scale (StRESS) is a self-report measure of environmental stressors appropriate for students in Advanced Placement (AP) and International Baccalaureate (IB) courses. We developed the StRESS…

  2. Resting heart rate variability after yogic training and swimming: A prospective randomized comparative trial

    PubMed Central

    Sawane, Manish Vinayak; Gupta, Shilpa Sharad

    2015-01-01

    Context: Resting heart rate variability (HRV) is a measure of the modulation of autonomic nervous system (ANS) at rest. Increased HRV achieved by the exercise is good for the cardiovascular health. However, prospective studies with comparison of the effects of yogic exercises and those of other endurance exercises like walking, running, and swimming on resting HRV are conspicuous by their absence. Aims: Study was designed to assess and compare the effects of yogic training and swimming on resting HRV in normal healthy young volunteers. Settings and Design: Study was conducted in Department of Physiology in a medical college. Study design was prospective randomized comparative trial. Subjects and Methods: One hundred sedentary volunteers were randomly ascribed to either yoga or swimming group. Baseline recordings of digital electrocardiogram were done for all the subjects in cohorts of 10. After yoga training and swimming for 12 weeks, evaluation for resting HRV was done again. Statistical Analysis Used: Percentage change for each parameter with yoga and swimming was compared using unpaired t-test for data with normal distribution and using Mann-Whitney U test for data without normal distribution. Results: Most of the HRV parameters improved statistically significantly by both modalities of exercise. However, some of the HRV parameters showed statistically better improvement with yoga as compared to swimming. Conclusion: Practicing yoga seems to be the mode of exercise with better improvement in autonomic functions as suggested by resting HRV. PMID:26170587

  3. High-rate activated sludge communities have a distinctly different structure compared to low-rate sludge communities, and are less sensitive towards environmental and operational variables.

    PubMed

    Meerburg, Francis A; Vlaeminck, Siegfried E; Roume, Hugo; Seuntjens, Dries; Pieper, Dietmar H; Jauregui, Ruy; Vilchez-Vargas, Ramiro; Boon, Nico

    2016-09-01

    High-rate activated sludge processes allow for the recovery of organics and energy from wastewaters. These systems are operated at a short sludge retention time and high sludge-specific loading rates, which results in a higher sludge yield and better digestibility than conventional, low-rate activated sludge. Little is known about the microbial ecology of high-rate systems. In this work, we address the need for a fundamental understanding of how high-rate microbial communities differ from low-rate communities. We investigated the high-rate and low-rate communities in a sewage treatment plant in relation to environmental and operational variables over a period of ten months. We demonstrated that (1) high-rate and low-rate communities are distinctly different in terms of richness, evenness and composition, (2) high-rate community dynamics are more variable and less shaped by deterministic factors compared to low-rate communities, (3) sub-communities of continuously core and transitional members are more shaped by deterministic factors than the continuously rare members, both in high-rate and low-rate communities, and (4) high-rate community members showed a co-occurrence pattern similar to that of low-rate community members, but were less likely to be correlated to environmental and operational variables. These findings provide a basis for further optimization of high-rate systems, in order to facilitate resource recovery from wastewater. PMID:27183209

  4. Radiolytic hydrogen production from process vessels in HB line - production rates compared to evolution rates and discussion of LASL reviews

    SciTech Connect

    Bibler, N.E.

    1992-11-12

    Hydrogen production from radiolysis of aqueous solutions can create a safety hazard since hydrogen is flammable. At times this production can be significant, especially in HB line where nitric acid solutions containing high concentrations of Pu-238, an intense alpha emitter, are processed. The hydrogen production rates from these solutions are necessary for safety analyses of these process systems. The methods and conclusions of hydrogen production rate tests are provided in this report.

  5. Acceleration of atherogenesis in ApoE−/− mice exposed to acute or low-dose-rate ionizing radiation

    PubMed Central

    Mancuso, Mariateresa; Pasquali, Emanuela; Braga-Tanaka, Ignacia; Tanaka, Satoshi; Pannicelli, Alessandro; Giardullo, Paola; Pazzaglia, Simonetta; Tapio, Soile; Atkinson, Michael J.; Saran, Anna

    2015-01-01

    There is epidemiological evidence for increased non-cancer mortality, primarily due to circulatory diseases after radiation exposure above 0.5 Sv. We evaluated the effects of chronic low-dose rate versus acute exposures in a murine model of spontaneous atherogenesis. Female ApoE−/− mice (60 days) were chronically irradiated for 300 days with gamma rays at two different dose rates (1 mGy/day; 20 mGy/day), with total accumulated doses of 0.3 or 6 Gy. For comparison, age-matched ApoE−/− females were acutely exposed to the same doses and sacrificed 300 days post-irradiation. Mice acutely exposed to 0.3 or 6 Gy showed increased atherogenesis compared to age-matched controls, and this effect was persistent. When the same doses were delivered at low dose rate over 300 days, we again observed a significant impact on global development of atherosclerosis, although at 0.3 Gy effects were limited to the descending thoracic aorta. Our data suggest that a moderate dose of 0.3 Gy can have persistent detrimental effects on the cardiovascular system, and that a high dose of 6 Gy poses high risks at both high and low dose rates. Our results were clearly nonlinear with dose, suggesting that lower doses may be more damaging than predicted by a linear dose response. PMID:26359350

  6. Acceleration of atherogenesis in ApoE-/- mice exposed to acute or low-dose-rate ionizing radiation.

    PubMed

    Mancuso, Mariateresa; Pasquali, Emanuela; Braga-Tanaka, Ignacia; Tanaka, Satoshi; Pannicelli, Alessandro; Giardullo, Paola; Pazzaglia, Simonetta; Tapio, Soile; Atkinson, Michael J; Saran, Anna

    2015-10-13

    There is epidemiological evidence for increased non-cancer mortality, primarily due to circulatory diseases after radiation exposure above 0.5 Sv. We evaluated the effects of chronic low-dose rate versus acute exposures in a murine model of spontaneous atherogenesis. Female ApoE-/- mice (60 days) were chronically irradiated for 300 days with gamma rays at two different dose rates (1 mGy/day; 20 mGy/day), with total accumulated doses of 0.3 or 6 Gy. For comparison, age-matched ApoE-/- females were acutely exposed to the same doses and sacrificed 300 days post-irradiation. Mice acutely exposed to 0.3 or 6 Gy showed increased atherogenesis compared to age-matched controls, and this effect was persistent. When the same doses were delivered at low dose rate over 300 days, we again observed a significant impact on global development of atherosclerosis, although at 0.3 Gy effects were limited to the descending thoracic aorta. Our data suggest that a moderate dose of 0.3 Gy can have persistent detrimental effects on the cardiovascular system, and that a high dose of 6 Gy poses high risks at both high and low dose rates. Our results were clearly nonlinear with dose, suggesting that lower doses may be more damaging than predicted by a linear dose response. PMID:26359350

  7. Patency rate and complications of polytetrafluoroethylene grafts compared with polyurethane grafts for hemodialysis access

    PubMed Central

    2010-01-01

    Background The survival of hemodialysis patients requiring dialysis depends on the long-term functioning and patency of the vascular access. Prosthetic vascular grafts are inevitably used for patients whose vessels are unsuitable for an autogenous arteriovenous (AV) fistula. The purpose of this study was to compare the patency rate and associated complications using different types of grafts. Methods This prospective study was conducted on patients who did not have an appropriate vein for arteriovenous fistula from January 2004 through July 2006. They were divided into two groups, sex, age, and basic data matched. Polytetrafluoroethylene (PTFE) and polyurethane (PVAG) were the two types of grafts used in this study. The functionality of the graft was assessed immediately 1 day and 2 weeks after operation. The clinical follow-up was performed each 3 months until 24 months. Results One-year patency rate was reported to be 64% and 52% in the PTFE and PVAG groups, respectively. There was no significant difference in 1-year (64% versus 52%) and 2-year (49% versus 41%) patency rate of the PTFE and PVAG grafts used as vascular access. There was also no difference between the numbers of complications reported in the two groups. Conclusion It could be concluded that either PTFE or PVAG grafts can be used with the same expected outcomes. PMID:20218943

  8. Cohort and duration patterns among Asian immigrants: Comparing trends in obesity and self-rated health

    PubMed Central

    Ro, Annie; Geronimus, Arline; Bound, John; Griffith, Derek; Gee, Gilbert

    2015-01-01

    Many studies, but not all, suggest that immigrant health worsens with duration of residence in the U.S. Cohort effects may explain the inconsistent findings; not only are cohort effects confounded with duration, but the timing of entry into the US may also create qualitatively different migration experiences. The present study tests for duration and cohort patterns among Asian immigrants to the United States across six year-of-entry cohorts (pre-1980, 1981-1985, 1986-1990, 1991-1995, 1996-2000, 2001-2005). Data come from the Asian American sample (n=44,002) from the 1994-2009 waves of the National Health Interview Survey. The data show cohort differences for self-rated health, such that more recent cohorts showed improved baseline health compared to older cohorts. After accounting for cohorts, there was no significant change in self-rated health by duration. Older cohorts actually showed improving self-rated health with longer duration. Obesity showed the opposite pattern; there were no differences across cohorts, but duration in the United States correlated with higher obesity. These results imply that immigrant health is not simply an issue of duration and adaptation, but underscore the utility of considering cohorts as broader contexts of migration. Collectively, the results encourage future research that more carefully examines the etiological mechanisms that drive immigrant health. PMID:25879262

  9. Comparing Occupational Health and Safety Management System Programming with Injury Rates in Poultry Production.

    PubMed

    Autenrieth, Daniel A; Brazile, William J; Douphrate, David I; Román-Muñiz, Ivette N; Reynolds, Stephen J

    2016-01-01

    Effective methods to reduce work-related injuries and illnesses in animal production agriculture are sorely needed. One approach that may be helpful for agriculture producers is the adoption of occupational health and safety management systems. In this replication study, the authors compared the injury rates on 32 poultry growing operations with the level of occupational health and safety management system programming at each farm. Overall correlations between injury rates and programming level were determined, as were correlations between individual management system subcomponents to ascertain which parts might be the most useful for poultry producers. It was found that, in general, higher levels of occupational health and safety management system programming were associated with lower rates of workplace injuries and illnesses, and that Management Leadership was the system subcomponent with the strongest correlation. The strength and significance of the observed associations were greater on poultry farms with more complete management system assessments. These findings are similar to those from a previous study of the dairy production industry, suggesting that occupational health and safety management systems may hold promise as a comprehensive way for producers to improve occupational health and safety performance. Further research is needed to determine the effectiveness of such systems to reduce farm work injuries and illnesses. These results are timely given the increasing focus on occupational safety and health management systems. PMID:27409413

  10. Rapid Circumstellar Disk Evolution and an Accelerating Star Formation Rate in the Infrared Dark Cloud M17 SWex

    NASA Astrophysics Data System (ADS)

    Povich, Matthew S.; Townsley, Leisa K.; Robitaille, Thomas P.; Broos, Patrick S.; Orbin, Wesley T.; King, Robert R.; Naylor, Tim; Whitney, Barbara A.

    2016-07-01

    We present a catalog of 840 X-ray sources and first results from a 100 ks Chandra X-ray Observatory imaging study of the filamentary infrared (IR) dark cloud G014.225–00.506, which forms the central regions of a larger cloud complex known as the M17 southwest extension (M17 SWex). In addition to the rich population of protostars and young stellar objects with dusty circumstellar disks revealed by archival data from the Spitzer Space Telescope, we discover a population of X-ray-emitting, intermediate-mass pre-main-sequence stars that lack IR excess emission from circumstellar disks. We model the IR spectral energy distributions of this source population to measure its mass function and place new constraints on the destruction timescales for the inner dust disk for 2–8 M ⊙ stars. We also place a lower limit on the star formation rate (SFR) and find that it is quite high (\\dot{M}≥slant 0.007 M ⊙ yr‑1), equivalent to several Orion Nebula Clusters in G14.225–0.506 alone, and likely accelerating. The cloud complex has not produced a population of massive, O-type stars commensurate with its SFR. This absence of very massive (≳20 M ⊙) stars suggests that either (1) M17 SWex is an example of a distributed mode of star formation that will produce a large OB association dominated by intermediate-mass stars but relatively few massive clusters, or (2) the massive cores are still in the process of accreting sufficient mass to form massive clusters hosting O stars.

  11. Assessment of survival rates compared according to the Tamai and Yamano classifications in fingertip replantations

    PubMed Central

    Dadaci, Mehmet; Ince, Bilsev; Altuntas, Zeynep; Bitik, Ozan; Kamburoglu, Haldun Onuralp; Uzun, Hakan

    2016-01-01

    Background: The fingertip is the most frequently injured and amputated segment of the hand. There are controversies about defining clear indications for microsurgical replantation. Many classification systems have been proposed to solve this problem. No previous study has simultaneously correlated different classification systems with replant survival rate. The aim of the study is to compare the outcomes of fingertip replantations according to Tamai and Yamano classifications. Materials and Methods: 34 consecutive patients who underwent fingertip replantation between 2007 and 2014 were retrospectively reviewed with respect to the Tamai and Yamano classifications. The medical charts from record room were reviewed. The mean age of the patients was 36.2 years. There were 30 men and 4 women. All the injuries were complete amputations. Of the 34 fingertip amputations, 19 were in Tamai zone 2 and 15 were in Tamai zone 1. When all the amputations were grouped in reference to the Yamano classification, 6 were type 1 guillotine, 8 were type 2 crush and 20 were type 3 crush avulsions. Results: Of the 34 fingertips, 26 (76.4%) survived. Ten (66.6%) of 15 digits replanted in Tamai zone 1 and 16 (84.2%) of 19 digits replanted in Tamai zone 2 survived. There were no replantation failures in Yamano type 1 injuries (100%) and only two failed in Yamano type 2 (75%). Replantation was successful in 14 of 20 Yamano type 3 injuries, but six failed (70%). The percentage of success rates was the least in the hybridized groups of Tamai zone 1-Yamano type 2 and Tamai zone 1-Yamano type 3. Although clinically distinct, the survival rates between the groups were not statistically significantly different. Conclusions: The level and mechanism of injury play a decisive role in the success of fingertip replantation. Success rate increases in proximal fingertip amputations without crush injury. PMID:27512220

  12. Comparative rates of photolysis of polychlorinated dibenzofurans in organic solvents and in aqueous solutions

    SciTech Connect

    Dung, M.H. ); O'Keefe, P.W. State Univ. of New York, Albany, NY )

    1994-04-01

    A generator-column technique was used to prepare aqueous solutions of polychlorinated dibenzofurans (PCDFs). The photolysis rate constants of 2,7-di-, 2,3,7,8-tetra-, and 1,2,7,8-tetra-CDF in aqueous solution irradiated at 300 nm were 1.3, 0.45, and 0.36 h[sup [minus]1], respectively. These photolysis rates were 4-15 times faster than the photolysis rates in organic solutions and, in the cases of 2,7-di CDF and 1,2,7,8-tetra-CDF, 20 times faster than in 60% acetonitrile/water. Thus, a solvent mixture of acetonitrile and water should not be used to study the photolysis of PCDFs in aqueous solution. The contribution of dechlorination to the overall loss of the PCDF compounds was determined. It was found that 10%, 70%, and 50% of photodecomposed 2,7-di-, 1,2,7,8-tetra-, and 2,3,7,8-tetra-CDF, respectively, were dechlorinated under 300-nm irradiation in hexane, compared with <1%, 17%, and 20% in water. Dechlorination may therefore be a major process in the photodecomposition of higher chlorinated PCDFs in hydrocarbon solvents but not in water. These results suggest that the mechanism of photolysis of PCDFs in water differs from that in organic solvents. It was also found that the sunlight photolysis rates of PCDFs in natural water were enhanced by indirect or sensitized photoreactions of chemicals naturally occurring in water. 34 refs., 2 figs., 4 tabs.

  13. Can Student Self-Ratings Be Compared with Peer Ratings? A Study of Measurement Invariance of Multisource Feedback

    ERIC Educational Resources Information Center

    Lee, Keng-Lin; Tsai, Shih-Li; Chiu, Yu-Ting; Ho, Ming-Jung

    2016-01-01

    Measurement invariance is a prerequisite for comparing measurement scores from different groups. In medical education, multi-source feedback (MSF) is utilized to assess core competencies, including the professionalism. However, little attention has been paid to the measurement invariance of assessment instruments; that is, whether an instrument…

  14. Literacy Acceleration and the Key Stage 3 English Strategy - Comparing Two Approaches for Secondary-Age Pupils with Literacy Difficulties

    ERIC Educational Resources Information Center

    Lingard, Tony

    2005-01-01

    Literacy for pupils in the secondary phase of education is a key concern for practitioners and policy makers alike. Tony Lingard is the SENCo at a large comprehensive school in the south-west of England but he is also involved in staff development and school improvement initiatives across the UK. Literacy Acceleration is an intervention strategy…

  15. 41 CFR 102-117.230 - Must I compare costs between a contract or a rate tender and the commuted rate system before...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Must I compare costs between a contract or a rate tender and the commuted rate system before choosing which method to use? 102-117.230 Section 102-117.230 Public Contracts and Property Management Federal Property...

  16. 41 CFR 102-117.230 - Must I compare costs between a contract or a rate tender and the commuted rate system before...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Must I compare costs between a contract or a rate tender and the commuted rate system before choosing which method to use? 102-117.230 Section 102-117.230 Public Contracts and Property Management Federal Property...

  17. 41 CFR 102-117.230 - Must I compare costs between a contract or a rate tender and the commuted rate system before...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Must I compare costs between a contract or a rate tender and the commuted rate system before choosing which method to use? 102-117.230 Section 102-117.230 Public Contracts and Property Management Federal Property...

  18. 41 CFR 102-117.230 - Must I compare costs between a contract or a rate tender and the commuted rate system before...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false Must I compare costs between a contract or a rate tender and the commuted rate system before choosing which method to use? 102-117.230 Section 102-117.230 Public Contracts and Property Management Federal Property...

  19. 41 CFR 102-117.230 - Must I compare costs between a contract or a rate tender and the commuted rate system before...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Must I compare costs between a contract or a rate tender and the commuted rate system before choosing which method to use? 102-117.230 Section 102-117.230 Public Contracts and Property Management Federal Property...

  20. Procedure to estimate maximum ground acceleration from macroseismic intensity rating: application to the Lima, Perú data from the October-3-1974-8.1-Mw earthquake

    NASA Astrophysics Data System (ADS)

    Ocola, L.

    2008-01-01

    Post-disaster reconstruction management of urban areas requires timely information on the ground response microzonation to strong levels of ground shaking to minimize the rebuilt-environment vulnerability to future earthquakes. In this paper, a procedure is proposed to quantitatively estimate the severity of ground response in terms of peak ground acceleration, that is computed from macroseismic rating data, soil properties (acoustic impedance) and predominant frequency of shear waves at a site. The basic mathematical relationships are derived from properties of wave propagation in a homogeneous and isotropic media. We define a Macroseismic Intensity Scale IMS as the logarithm of the quantity of seismic energy that flows through a unit area normal to the direction of wave propagation in unit time. The derived constants that relate the IMS scale and peak acceleration agree well with coefficients derived from a linear regression between MSK macroseismic rating and peak ground acceleration for historical earthquakes recorded at a strong motion station, at IGP's former headquarters, since 1954. The procedure was applied to 3-October-1974 Lima macroseismic intensity data at places where there was geotechnical data and predominant ground frequency information. The observed and computed peak acceleration values, at nearby sites, agree well.

  1. A simple algorithm for predicting proton SEU rates in space compared to the rates measured on the CRRES satellite

    SciTech Connect

    Reed, R.A.; McNulty, P.J.; Beauvais, W.J.; Abdel-Kader, W.G. . Dept. of Physics and Astronomy); Stassinopoulos, E.G.; Barth, J.C.L. )

    1994-12-01

    A new simulation code, the Clemson Omnidirectional Spallation Model for Interaction in Circuits (COSMIC), is described and its predictions agree with SEU data from four devices flown as part of the microelectronics package experiment on the CRRES satellite. The code uses CUPID for determining the energy depositions in the sensitive volumes; it allows proton exposures with arbitrary angles of incidence including random omnidirectional exposure; and the user specifies the thickness of shielding on six sides of the sensitive volume. COSMIC is used as part of an algorithm developed to predict the rate proton induced single event upsets occur in the space radiation environment given by AP-8. In testing the algorithm, the position coordinates are taken from the satellite's ephemeris data, but calculations based on position coordinates from orbital codes were also in agreement with the measured values.

  2. Comparing Time-Dependent Geomagnetic and Atmospheric Effects on Cosmogenic Nuclide Production Rate Scaling

    NASA Astrophysics Data System (ADS)

    Lifton, N. A.

    2014-12-01

    A recently published cosmogenic nuclide production rate scaling model based on analytical fits to Monte Carlo simulations of atmospheric cosmic ray flux spectra (both of which agree well with measured spectra) (Lifton et al., 2014, Earth Planet. Sci. Lett. 386, 149-160: termed the LSD model) provides two main advantages over previous scaling models: identification and quantification of potential sources of bias in the earlier models, and the ability to generate nuclide-specific scaling factors easily for a wide range of input parameters. The new model also provides a flexible framework for exploring the implications of advances in model inputs. In this work, the scaling implications of two recent time-dependent spherical harmonic geomagnetic models spanning the Holocene will be explored. Korte and Constable (2011, Phys. Earth Planet. Int. 188, 247-259) and Korte et al. (2011, Earth Planet. Sci. Lett. 312, 497-505) recently updated earlier spherical harmonic paleomagnetic models used by Lifton et al. (2014) with paleomagnetic measurements from sediment cores in addition to archeomagnetic and volcanic data. These updated models offer improved accuracy over the previous versions, in part to due to increased temporal and spatial data coverage. With the new models as input, trajectory-traced estimates of effective vertical cutoff rigidity (RC- the standard method for ordering cosmic ray data) yield significantly different time-integrated scaling predictions when compared to the earlier models. These results will be compared to scaling predictions using another recent time-dependent spherical harmonic model of the Holocene geomagnetic field by Pavón-Carrasco et al. (2014, Earth Planet. Sci. Lett. 388, 98-109), based solely on archeomagnetic and volcanic paleomagnetic data, but extending to 14 ka. In addition, the potential effects of time-dependent atmospheric models on LSD scaling predictions will be presented. Given the typical dominance of altitudinal over

  3. Comparative study of ion acceleration by linearly polarized laser pulses from optimized targets of solid and near-critical density

    NASA Astrophysics Data System (ADS)

    Bychenkov, V. Yu; Brantov, A. V.; Govras, E. A.

    2016-03-01

    The results of a 3D optimization study of ion acceleration from ultrathin solid density foils (Brantov et al 2015 Phys. Rev. Spec. Top. Accel. Beams 18 021301) are complemented with an improved analytic model of the directed Coulomb explosion. Similarly to optimizing overdense targets, we also optimize low-density targets to obtain maximum ion energy, motivated by progress in producing a new generation of low-density slab targets whose density can be very homogeneous and as low as the relativistic critical density. Using 3D simulations, we show that for the same laser pulse, the ion energy can be significantly increased with low-density targets. A new acceleration mechanism is responsible for such an increase. This mechanism is described qualitatively, and it explains an advantage of low-density targets for high-energy ion production by lasers.

  4. Benefit of single setting rate responsive ventricular pacing compared with fixed rate demand pacing in elderly patients.

    PubMed

    Gammage, M; Schofield, S; Rankin, I; Bennett, M; Coles, P; Pentecost, B

    1991-02-01

    In order to assess the value of a simple, single setting rate response option to VVI pacing, 12 patients (mean age 75.1 +/- 6.2, range 62-83 years, seven males, five females) with symptomatic complete heart block were entered into a double-blind, randomized crossover trial of VVI versus VVIR (single setting rate responsive) pacing using Medtronic Activitrax pacemakers. Assessment was by time taken in seconds (sec) and Borg scale symptom score (6-20) for simple activities (standing from chair x 30; walking 800 meters; 52 steps on stairs [slow and fast pace], and incremental, noninclined maximal treadmill exercise), performed after a 4-week period with the patient in each pacing mode. Times were significantly improved in VVIR mode for standing from chair [mean +/- SD] (78.7 +/- 22.5 vs 70.7 +/- 19.5 sec; P less than 0.05), for 800 m walk (1032 +/- 80 vs 885 +/- 59 sec; P less than 0.05), fast ascent of stairs (29.5 +/- 7.7 vs 26.5 +/- 5.6 sec; P less than 0.02), and treadmill exercise (626.7 +/- 189.5 vs 741.0 +/- 170.2 sec, P less than 0.005) although no difference in time for slow stair ascent was demonstrated. Symptom scores were significantly less in VVIR for standing from chair (12.7 +/- 2.8 vs 10.3 +/- 1.8; P less than 0.01), 800 m walk (10.9 +/- 2.7 vs 9.0 +/- 2.4; P less than 0.01), slow ascent of stairs (11.6 +/- 2.1 vs 10.0 +/- 2.0; P less than 0.01), and fast ascent of stairs (13.0 +/- 2.0 vs 11.7 +/- 1.9; P less than 0.02) but unchanged for treadmill exercise.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1706502

  5. Doppler-derived acceleration rate of right ventricular early filling as a measurement of right atrial pressure in chronic heart failure secondary to ischemic or idiopathic dilated cardiomyopathy.

    PubMed

    Scapellato, F; Eleuteri, E; Temporelli, P L; Imparato, A; Corrà, U; Giannuzzi, P

    1998-02-15

    This study demonstrates that a Doppler-derived tricuspid flow velocity pattern provides an accurate, feasible, and noninvasive method of estimating and monitoring mean right atrial pressure in patients with heart failure due to left ventricular systolic dysfunction, and who are both in sinus rhythm and atrial fibrillation. In particular, the acceleration rate of early right ventricular filling is a powerful and independent predictor of mean right atrial pressure. PMID:9485149

  6. The IMSI Procedure Improves Laboratory and Clinical Outcomes Without Compromising the Aneuploidy Rate When Compared to the Classical ICSI Procedure

    PubMed Central

    Luna, Daniel; Hilario, Roly; Dueñas-Chacón, Julio; Romero, Rocío; Zavala, Patricia; Villegas, Lucy; García-Ferreyra, Javier

    2015-01-01

    PURPOSE The intracytoplasmic morphologically selected sperm injection (IMSI) procedure has been associated with better laboratory and clinical outcomes in assisted reproduction technologies. Less information is available regarding the relationship between embryo aneuploidy rate and the IMSI procedure. The aim of this study is to compare the clinical outcomes and chromosomal status of IMSI-derived embryos with those obtained from intracytoplasmic sperm injection (ICSI) in order to establish a clearer view of the benefits of IMSI in infertile patients. METHODS We retrospectively analyzed a total of 11 cycles of IMSI and 20 cycles of ICSI with preimplantation genetic diagnosis. The fertilization rate, cleavage rate, embryo quality, blastocyst development, aneuploidy rate, pregnancy rate, implantation rate, and miscarriage rate were compared between the groups. RESULTS Similar rates of fertilization (70% and 73%), cleavage (98% and 100%), and aneuploidy (76.9% and 70.9%) were observed in the IMSI and ICSI groups, respectively. The IMSI group had significantly more good quality embryos at day 3 (95% vs 73%), higher blastocyst development rates (33% vs 19%), and greater number of hatching blastocysts (43% vs 28%), cycles with at least one blastocyst at day 5 (55% vs 35%), and blastocysts with good trophoectoderm morphology (21% vs 6%) compared with the ICSI group (P < 0.001). Significantly higher implantation rates were observed in the IMSI group compared with the ICSI group (57% vs 27%; P < 0.05). Pregnancy and miscarriage rates were similar in both groups (80% vs 50% and 0% vs 33%, respectively). CONCLUSION The IMSI procedure significantly improves the embryo quality/development by increasing the implantation rates without affecting the chromosomal status of embryos. There is a tendency for the IMSI procedure to enhance the pregnancy rates and lower the miscarriage rates when compared with ICSI. PMID:26609251

  7. A Comparative Study of Eight Finite-Rate Chemistry Kinetics for CO/H-2 Combustion

    SciTech Connect

    Marzouk, OA; ED, Huckaby

    2010-09-01

    We compare the performance and computational cost of 8 kinetic models (3 global and 5 elementary) that describe the finite-rate chemistry of syngas combustion. We apply them in simulating a turbulent jet flame with syngas diluted by 30% nitrogen. We model the turbulence by a modified k-epsilon model and the turbulence-chemistry interaction by the partially stirred reactor approach. To integrate the chemistry equations, we nominally use explicit fifth-order embedded Runge-Kutta ODE solver. But semi-implicit Bulirsch-Stoer and implicit Euler were also used. The computational time depends on the number of reaction steps and the ODE solver. Five models overpredict the maximum flame temperature (by 200 K-320 K). Two models underpredict it by 240 K and 580 K. The global model that is based on the Westbrook-Dryer (1981) model for hydrocarbon fuels gives the best agreement with measurements, and also has low computational demand. Therefore, it is recommended for modeling turbulent syngas flames.

  8. A study of the influence of the data acquisition system sampling rate on the accuracy of measured acceleration loads for transport aircraft

    NASA Technical Reports Server (NTRS)

    Whitehead, Julia H.

    1992-01-01

    A research effort was initiated at National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC), to describe the relationship between the sampling rate and the accuracy of acceleration loads obtained from the data acquisition system of a transport aircraft. An accelerometer was sampled and digitized at a rate of 100 samples per second onboard a NASA Boeing 737 (B-737) flight research aircraft. Numerical techniques were used to reconstruct 2.5 hours of flight data into its original input waveform and then re-sample the waveform into rates of 4, 8, 16, and 32 samples per second. Peak-between-means counting technique and power spectral analysis were used to evaluate each sampling rate using the 32 samples per second data as the comparison. This paper presents the results from these methods and includes in appendix A, the peak-between-means counting results used in a general fatigue analysis for each of the sampling rates.

  9. Seasonal differences in suicide birth rate in Alaska Natives compared to other populations.

    PubMed

    Kettl, P A; Collins, T; Sredy, M; Bixler, E O

    1997-01-01

    Seasonal differences in suicide birth rates among Alaska Natives and for populations at different latitudes (residents of the Yukon, Saskatchewan, Montana, Wyoming, and Pennsylvania) were investigated. Seasonal birth rates for the general population were similarly examined. Suicide birth rates showed small seasonal variations for Alaska Natives with summer births showing more suicides. However, at lower latitudes, suicide birth rates among other populations showed no seasonal differences. Hours of daily sunlight at the summer and winter solstice correlated with the proportion of suicide victims born during those seasons. Seasonal differences in birth rates of suicide victims correlated strongly with latitude and seasonal differences in daylight. General population birth rates did not show significant seasonal differences, and did not correlate with differences in latitude or sunlight length at the summer or winter solstice. PMID:9458541

  10. Applied Comparative Effectiveness Researchers Must Measure Learning Rates: A Commentary on Efficiency Articles

    ERIC Educational Resources Information Center

    Skinner, Christopher H.

    2010-01-01

    Almost all academic skills deficits can be conceptualized as learning rate problems as students are not failing to learn, but not learning rapidly enough. Thus, when selecting among various possible remedial procedures, educators need an evidence base that indicates which procedure results in the greatest increases in learning rates. Previous…

  11. Comparative rates of wind versus water erosion from a small semiarid watershed in southern Arizona, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Both wind erosion and water erosion can be serious land degradation processes in semi-arid dry-lands. However, the relative erosion rates of wind and water erosion have rarely been studied simultaneously and are poorly quantified. In this study, wind erosion and water erosion rates were simultaneous...

  12. Comparability of the Social Skills Improvement System to the Social Skills Rating System: A Norwegian Study

    ERIC Educational Resources Information Center

    Gamst-Klaussen, Thor; Rasmussen, Lene-Mari P.; Svartdal, Frode; Strømgren, Børge

    2016-01-01

    The Social Skills Improvement System-Rating Scales (SSIS-RS) is a multi-informant instrument assessing social skills and problem behavior in children and adolescents. It is a revised version of the Social Skills Rating System (SSRS). A Norwegian translation of the SSRS has been validated, but this has not yet been done for the Norwegian…

  13. A comparative study of high strain rate behavior of three martensitic steels

    NASA Astrophysics Data System (ADS)

    Last, H. R.; Garrett, R. K.; Rajendran, A. M.

    1996-05-01

    This paper describes the high strain rate response of HY100, HY130 and AF1410 steels determined from the split Hopkinson bar and quasi-static experiments under room and high temperatures. Differences in the macroscopic high strain rate response of these steels were observed. Metallurgical fracture surface analysis provided insight into the microstructural response and the observed macroscopic behavior of each steel.

  14. Comparative Survival [Rate] Study (CSS); Design and Analysis, 2002 Technical Report.

    SciTech Connect

    Bouwes, Nick; Petrosky, Charlie; Schaller, Howard

    2002-04-01

    Fisheries agencies and tribes have developed a multi-year program, the Comparative Survival Study (CSS), to obtain information to be used in monitoring and evaluating the impacts of the mitigation measures and actions (e.g., flow augmentation, spill, and transportation) under NMFS' Biological Opinion to recover listed stocks. Through 2001, the CSS has utilized PIT tagged yearling hatchery chinook that were tagged specifically for the CSS and PIT tagged wild chinook from all available marking efforts in the Snake River basin above Lower Granite Dam. We selected hatchery programs that would allow the opportunity to mark sufficient numbers of smolts to give enough returning adult fish that statistically rigorous smolt-to-adult survival rates could be computed. Since the CSS inception, hatchery fish that have consistently been used include spring/summer chinook tagged at McCall, Rapid River, Dworshak, and Lookingglass (Imnaha stock) hatcheries. The CSS has also included a group of spring chinook from Carson Hatchery in the lower Columbia River for planned upstream/downstream comparison. The wild stocks included chinook PIT tagged as parr (summer/fall tagging season) and smolts (spring tagging season) in each major tributary above Lower Granite Dam. Future years will see the CSS add wild and hatchery steelhead in the Snake River basin, hatchery steelhead in the Mid-Columbia River basin, hatchery yearling chinook in the Mid-Columbia River basin, and wild chinook in John Day River in the lower Columbia River. Each PIT (passive integrated transponder) tag has a unique code. The tags are glass encapsulated, 11 mm in length, and implanted into the fish's underbelly by a syringe. All attempts are made to make the PIT tagged fish as representative of their untagged cohorts as possible. At trapping sites, sampling and tagging occur over the entire migration season. At hatcheries, fish to tag are obtained across as wide a set of ponds and raceways as possible to allow effective

  15. The exercise heart rate profile in master athletes compared to healthy controls.

    PubMed

    Kwon, Osung; Park, Saejong; Kim, Young-Joo; Min, Sun-Yang; Kim, Yoo Ri; Nam, Gi-Byoung; Choi, Kee-Joon; Kim, You-Ho

    2016-07-01

    Endurance exercise protects the heart via effects on autonomic control of heart rate (HR); however, its effects on HR indices in healthy middle-aged men are unclear. This study compared HR profiles, including resting HR, increase in HR during exercise and HR recovery after exercise, in middle-aged athletes and controls. Fifty endurance-trained athletes and 50 controls (all male; mean age, 48·7 ± 5·8 years) performed an incremental symptom-limited exercise treadmill test. The electrocardiographic findings and HR profiles were evaluated. Maximal O2 uptake (52·6 ± 7·0 versus 34·8 ± 4·5 ml kg(-1)  min(-1) ; P<0·001) and the metabolic equivalent of task (15·4 ± 1·6 versus 12·2 ± 1·5; P<0·001) were significantly higher in athletes than in controls. Resting HR was significantly lower in athletes than in controls (62·8 ± 6·7 versus 74·0 ± 10·4 beats per minute (bpm), respectively; P<0·001). Athletes showed a greater increase in HR during exercise than controls (110·1 ± 11·0 versus 88·1 ± 15·4 bpm; P<0·001); however, there was no significant between-group difference in HR recovery at 1 min after cessation of exercise (22·9 ± 5·6 versus 21·3 ± 6·7 bpm; P = 0·20). Additionally, athletes showed a lower incidence of premature ventricular contractions (PVCs) during exercise (0·0% versus 24·0%; P<0·001). Healthy middle-aged men participating in regular endurance exercise showed more favourable exercise HR profiles and a lower incidence of PVCs during exercise than sedentary men. These results reflect the beneficial effect of endurance training on autonomic control of the heart. PMID:25532888

  16. Comparative sensitivity study and reading correction of various albedo dosimeters in neutron fields on the U-400M accelerator

    NASA Astrophysics Data System (ADS)

    Mokrov, Yu. V.; Morozov, S. V.; Shchegolev, V. Yu.

    2013-03-01

    The sensitivities of three types of albedo dosimeters are experimentally studied in U-400M accelerator radiation fields in the experimental hall (one point) and behind its shielding (three points). It is shown that the ratios of the sensitivity of the albedo dosimeter (AD) and the combined personal dosimeter (CPD) used earlier at the Joint Institute for Nuclear Research (JINR) to the sensitivity of the DVGN-01 dosimeter are constant within 25%. This allows the AD and CPD sensitivities obtained earlier at the JINR facilities to be used for correcting readings of the DVGN-01 now used at JINR for personal radiation monitoring. Correction coefficients are found for DVGN-01 readings behind the U-400M shielding. This has allowed a more reliable correction coefficient to be established for the Flerov Laboratory of Nuclear Reactions (FLNR).

  17. Comparative Ratings of Printed Nutrition Materials Developed by Industry and Government Producers.

    ERIC Educational Resources Information Center

    Holmes, Cheryl Lynn; Bunda, Mary Anne

    1983-01-01

    A study investigated the quality of supplemental, printed nutrition materials sponsored by the food industry and government agencies and evaluated their appropriateness for classroom instruction. Materials were rated by teachers, curriculum specialists, and nutrition specialists. (Authors/PP)

  18. Comparative investigation of three dose rate meters for their viability in pulsed radiation fields.

    PubMed

    Gotz, M; Karsch, L; Pawelke, J

    2015-06-01

    Pulsed radiation fields, characterized by microsecond pulse duration and correspondingly high pulse dose rates, are increasingly used in therapeutic, diagnostic and research applications. Yet, dose rate meters which are used to monitor radiation protection areas or to inspect radiation shielding are mostly designed, characterized and tested for continuous fields and show severe deficiencies in highly pulsed fields. Despite general awareness of the problem, knowledge of the specific limitations of individual instruments is very limited, complicating reliable measurements. We present here the results of testing three commercial dose rate meters, the RamION ionization chamber, the LB 1236-H proportional counter and the 6150AD-b scintillation counter, for their response in pulsed radiation fields of varied pulse dose and duration. Of these three the RamION proved reliable, operating in a pulsed radiation field within its specifications, while the other two instruments were only able to measure very limited pulse doses and pulse dose rates reliably. PMID:25978117

  19. Comparative study of ageing, heat treatment and accelerated carbonation for stabilization of municipal solid waste incineration bottom ash in view of reducing regulated heavy metal/metalloid leaching.

    PubMed

    Santos, Rafael M; Mertens, Gilles; Salman, Muhammad; Cizer, Özlem; Van Gerven, Tom

    2013-10-15

    This study compared the performance of four different approaches for stabilization of regulated heavy metal and metalloid leaching from municipal solid waste incineration bottom ash (MSWI-BA): (i) short term (three months) heap ageing, (ii) heat treatment, (iii) accelerated moist carbonation, and (iv) accelerated pressurized slurry carbonation. Two distinct types of MSWI-BA were tested in this study: one originating from a moving-grate furnace incineration operation treating exclusively household refuse (sample B), and another originating from a fluid-bed furnace incineration operation that treats a mixture of household and light industrial wastes (sample F). The most abundant elements in the ashes were Si (20-27 wt.%) and Ca (16-19 wt.%), followed by significant quantities of Fe, Al, Na, S, K, Mg, Ti, and Cl. The main crystalline substances present in the fresh ashes were Quartz, Calcite, Apatite, Anhydrite and Gehlenite, while the amorphous fraction ranged from 56 to 73 wt.%. The leaching values of all samples were compared to the Flemish (NEN 7343) and the Walloon (DIN 38414) regulations from Belgium. Batch leaching of the fresh ashes at natural pH showed that seven elements exceeded at least one regulatory limit (Ba, Cr, Cu, Mo, Pb, Se and Zn), and that both ashes had excess basicity (pH > 12). Accelerated carbonation achieved significant reduction in ash basicity (9.3-9.9); lower than ageing (10.5-12.2) and heat treatment (11.1-12.1). For sample B, there was little distinction between the leaching results of ageing and accelerated carbonation with respect to regulatory limits; however carbonation achieved comparatively lower leaching levels. Heat treatment was especially detrimental to the leaching of Cr. For sample F, ageing was ineffective and heat treatment had marginally better results, while accelerated carbonation delivered the most effective performance, with slurry carbonation meeting all DIN limits. Slurry carbonation was deemed the most

  20. Comparing mutation rates under the Luria-Delbrück protocol.

    PubMed

    Zheng, Qi

    2016-06-01

    Comparison of microbial mutation rates under the Luria-Delbrück protocol is a routine laboratory task. However, execution of this important task has been hampered by the lack of proper statistical methods. Visual inspection or improper use of the t test and the Mann-Whitney test can impair the quality of genetic research. This paper proposes a unified framework for constructing likelihood ratio tests that overcome three important obstacles to the proper comparison of microbial mutation rates. Specifically, algorithms for likelihood ratio tests have been devised that allow for partial plating, differential growth rates and unequal terminal cell population sizes. The new algorithms were assessed by computer simulations. In addition, a strategy for multiple comparison was illustrated by reanalyzing the experimental data from a study of bacterial resistance against tuberculosis antibiotics. PMID:27188462

  1. Biological Manipulation of Migration Rate: The Use of Advanced Photoperiod to Accelerate Smoltification in Yearling Chinook Salmon, Annual Report 1989.

    SciTech Connect

    Giorgi, Albert E.; Muir, William D.; Zaugg, Waldo S.

    1991-01-01

    Research was conducted to assess the feasibility of biologically manipulating physiological development and migratory behavior of yearling spring chinook salmon, Oncorhynchus tshawytscha. At Dworshak National Fish Hatchery, treatment groups were exposed to a variety of advanced photoperiod cycles preceding release to accelerate smolt development. Physiological development and migratory performance were described for all groups. The treatments included a 14-week exposure to a 3-month advanced photoperiod cycle, an 18-week exposure to a 3-month advanced photoperiod cycle, and an 18-week exposure to a 4-month advanced photoperiod cycle. Two additional groups, an 18-week exposure to a 3-month advanced photoperiod and a control equivalent, were reared at an elevated water temperature (11{degrees}C) for 2 weeks prior to release. Results indicated that the treated fish which were the most physiologically advanced at release were detected in the highest proportion at collector dams and also migrated fastest downstream. 26 refs., 10 figs., 5 tabs.

  2. The Effects of Vestibular Stimulation Rate and Magnitude of Acceleration on Central Pattern Generation for Chest Wall Kinematics in Preterm Infants

    PubMed Central

    Zimmerman, Emily; Barlow, Steven M.

    2013-01-01

    Objective To examine the role of vestibular inputs on respiratory and oromotor systems in healthy preterm infants. Study Design 27 preterm infants were quasi-randomly assigned to either the VestibuGlide treatment or control groups. VestibuGlide infants were held in a developmentally supportive position, given a pacifier and received a series of vestibular stimuli, counterbalanced across rate and acceleration conditions, 15 minutes 3x/day for 10 days. The control infants were also held in a developmentally supportive position, given a pacifier for 15 minutes 3x/day for 10 days but did not receive the VestibuGlide stimulation. Result A multi-level regression model revealed that treatment infants increased their respiratory rate in response to vestibular stimulus and that the highest level of vestibular acceleration delivered to the infants (0.51 m/s2) resulted in a significant increase in breaths per minute. Conclusion Vestibular stimulation delivered to preterm infants prior to scheduled feeds effectively modulates respiratory rate and resets the respiratory central pattern generator. PMID:22157627

  3. The rate constant for radiative association of HF: Comparing quantum and classical dynamics

    SciTech Connect

    Gustafsson, Magnus Monge-Palacios, M.; Nyman, Gunnar

    2014-05-14

    Radiative association for the formation of hydrogen fluoride through the A{sup 1}Π → X{sup 1}Σ{sup +} and X{sup 1}Σ{sup +} → X{sup 1}Σ{sup +} transitions is studied using quantum and classical dynamics. The total thermal rate constant is obtained for temperatures from 10 K to 20 000 K. Agreement between semiclassical and quantum approaches is observed for the A{sup 1}Π → X{sup 1}Σ{sup +} rate constant above 2000 K. The agreement is explained by the fact that the corresponding cross section is free of resonances for this system. At temperatures below 2000 K we improve the agreement by implementing a simplified semiclassical expression for the rate constant, which includes a quantum corrected pair distribution. The rate coefficient for the X{sup 1}Σ{sup +} → X{sup 1}Σ{sup +} transition is calculated using Breit–Wigner theory and a classical formula for the resonance and direct contributions, respectively. In comparison with quantum calculations the classical formula appears to overestimate the direct contribution to the rate constant by about 12% for this transition. Below about 450 K the resonance contribution is larger than the direct, and above that temperature the opposite holds. The biggest contribution from resonances is at the lowest temperature in the study, 10 K, where it is more than four times larger than the direct. Below 1800 K the radiative association rate constant due to X{sup 1}Σ{sup +} → X{sup 1}Σ{sup +} transitions dominates over A{sup 1}Π → X{sup 1}Σ{sup +}, while above that temperature the situation is the opposite.

  4. Lower confidence bound on the percentage improvement in comparing two failure rates

    NASA Astrophysics Data System (ADS)

    Angus, John E.

    1992-06-01

    It is often necessary to determine whether a design change in a product has actually improved its failure rate, and to compute a lower confidence bound on the percentage of failure rate improvement affected by the change. This paper shows how such a bound can be computed based on certain test data. The main result of the paper is a special case of an equivalent result derived in Lehmann for hypothesis testing and used extensively in applied statistics. However, it is not well-known in its confidence interval form, nor is it extensively reported in reliability methods books, and its derivation is important in reliability testing.

  5. What factors shape rates of phenotypic evolution? A comparative study of cranial morphology of four mammalian clades.

    PubMed

    Cooper, N; Purvis, A

    2009-05-01

    Understanding why rates of morphological evolution vary is a major goal in evolutionary biology. Classical work suggests that body size, interspecific competition, geographic range size and specialization may all be important, and each may increase or decrease rates of evolution. Here, we investigate correlates of proportional evolutionary rates in phalangeriform possums, phyllostomid bats, platyrrhine monkeys and marmotine squirrels, using phylogenetic comparative methods. We find that the most important correlate is body size. Large species evolve the fastest in all four clades, and there is a nonlinear relationship in platyrrhines and phalangeriformes, with the slowest evolution in species of intermediate size. We also find significant increases in rate with high environmental temperature in phyllostomids, and low mass-specific metabolic rate in marmotine squirrels. The mechanisms underlying these correlations are uncertain and appear to be size specific. We conclude that there is significant variation in rates of evolution, but that its meaning is not yet clear. PMID:21462402

  6. The Rate of Return to Educational Investment in China: A Comparative Commentary

    ERIC Educational Resources Information Center

    Li, Fengliang; Zhao, Yandong; Morgan, W. John

    2011-01-01

    This article comments on several features of the rate of return (ROR) to educational investment in China: first, the ROR to educational investment has increased with the expansion of educational provision since the 1980s. Second, the greater the educational provision, the greater the ROR. Third, the ROR in urban areas is more than that in rural…

  7. Comparing Participants' Rating and Compendium Coding to Estimate Physical Activity Intensities

    ERIC Educational Resources Information Center

    Masse, Louise C.; Eason, Karen E.; Tortolero, Susan R.; Kelder, Steven H.

    2005-01-01

    This study assessed agreement between participants' rating (PMET) and compendium coding (CMET) of estimating physical activity intensity in a population of older minority women. As part of the Women on the Move study, 224 women completed a 7-day activity diary and wore an accelerometer for 7 days. All activities recorded were coded using PMET and…

  8. A Study of the Comparability of Speaking Proficiency Interview Ratings across Three Government Language Training Agencies.

    ERIC Educational Resources Information Center

    Clark, John L. D.

    A study of the reliability of the proficiency ratings scale and techniques used by three federal government agencies--the Central Intelligence Agency, the Defense Language Institute, and the Foreign Service Institute (FSI)--to test employees' oral language proficiency in French and German had two randomly selected two-person teams of testers from…

  9. Comparing the Effects of Unknown-Known Ratios on Word Reading Learning versus Learning Rates

    ERIC Educational Resources Information Center

    Joseph, Laurice M.; Nist, Lindsay M.

    2006-01-01

    An extension of G. L. Cates et al. (2003) investigation was conducted to determine if students' cumulative learning rates would be superior for words read under a traditional drill and practice condition (as they were for spelling in the previous study) than under interspersal conditions of varying ratios of unknown to known words. Participants…

  10. Comparative capture rate responses of mosquito vectors to light trap and human landing collection methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Capture rate responses of female Aedes albopictus Skuse, Anopheles quadrimaculatus Say, Culex nigripalpus Theobald, Culex quinquefasciatus Say, and Ochlerotatus triseriatus (Wiedemann) to CDC-type light trap (LT) and human landing (HL) collection methods were observed and evaluated for congruency wi...

  11. Comparing OSL and CN techniques for dating fluvial terraces and estimating surface process rates in Pamir

    NASA Astrophysics Data System (ADS)

    Fuchs, Margret; Gloaguen, Richard; Pohl, Eric; Sulaymonova, Vasila; Merchel, Silke; Rugel, Georg

    2014-05-01

    The quantification of surface process rates is crucial for understanding the topographic evolution of high mountains. Spatial and temporal variations in fluvial incision and basin-wide erosion enable to decipher the role of tectonic and climatic drivers. The Pamir is peculiar in both aspects because of its location at the western end of the India-Asia collision zone, and its position at the edge of two atmospheric circulation systems, the Westerlies and the Indian Summer Monsoon. The architecture of the Panj river network indicates prominent variations across the main tectonic structures of the Pamir. The trunk stream, deflects from the predominantly westward river orientation and cuts across the southern and central Pamir domes before doubling back to the west and leaving the orogen. Optically stimulated luminescence (OSL) dating of fluvial terraces reveals short-term sedimentation along the trunk stream during the last ~25 kyr. The agreement of OSL results to new exposure ages based on the cosmogenic nuclide (CN) 10Be confirms accurate terrace age modelling and treatment of incomplete bleaching. The consistent terrace sedimentation and exposure ages suggest also fast terrace abandonment and rapid onset of incision. Considerable differences in terrace heights reflect high spatial variations of fluvial incision, independent of time interval, change in rock type or catchment increase. Highest rates of (5.9 ± 1.1) mm/yr to (10.0 ± 2.0) mm/yr describe the fluvial dynamic across the Shakhdara Dome and that related to the Darvaz Fault Zone. Lower rates of (3.9 ± 0.6) mm/yr to (4.5 ± 0.7) mm/yr indicate a transient stage north of the Yazgulom Dome. Fluvial incision decreases to rates ranging from (1.7 ± 0.3) mm/yr to (3.9 ± 0.7) mm/yr in graded river reaches associated to southern dome boundaries. The pattern agrees to the interpretation of successive upstream river captures across the southern and central Pamir domes inferred from morphometric analyses of river

  12. Measurement of plutonium and other actinide elements at the center for accelerator mass spectrometry: a comparative assessments of competing techniques

    SciTech Connect

    Hamilton, T H; McAninch, J

    1999-02-01

    initiatives. One potential measurement technique for meeting these requirements is accelerator mass spectrometry (AMS). AMS is a widely accepted analytical technique for measurement of isotopes such as 14 C, 26 Al, 36 Cl (Vogel et al., 1995) but has only recently been demonstrated for the quantitative detection of actinides (Fifield et al., 1996). The Center for Accelerator Mass Spectrometry (CAMS) at the Lawrence Livermore National Laboratory (LLNL) operates the most versatile and most productive AMS instrument in the world (Roberts et al., 1996). The addition of a Heavy Ion Beamline and associated hardware for actinide detection are in an advanced stage of development. Detection limits for actinide elements are expected to be on the order of 1 ´ 10 6 atoms (~0.5 fg) or lower with an initial measurement capacity of a few hundred samples per year. The ultimate detection sensitivity is expected to be ~1 ´ 10 5 atoms. Here we provide a review of non-conventional measurement techniquesÑincluding AMSÑfor the determination of low-levels of 239 Pu and other actinide elements in environmental samples. We include a discussion of potential measurement interferences and sample preparation requirements for the different techniques, and outline our proposed AMS system design and strategic approach for the development of low-level actinide detection capability at CAMS.

  13. Comparative Study of Inguinal Hernia Repair Rates After Radical Prostatectomy or External Beam Radiotherapy

    SciTech Connect

    Lughezzani, Giovanni; Sun, Maxine; Perrotte, Paul; Alasker, Ahmed; Jeldres, Claudio; Isbarn, Hendrik; Budaeus, Lars; Lattouf, Jean-Baptiste; Valiquette, Luc; Benard, Francois; Saad, Fred; Graefen, Markus; Montorsi, Francesco; Karakiewicz, Pierre I.

    2010-12-01

    Purpose: We tested the hypothesis that patients treated for localized prostate cancer with radical prostatectomy (RP) have a higher risk of requiring an inguinal hernia (IH) repair than their counterparts treated with external beam radiotherapy (EBRT). Methods and Materials: Within the Quebec Health Plan database, we identified 6,422 men treated with RP and 4,685 men treated with EBRT for localized prostate cancer between 1990 and 2000, in addition to 6,933 control patients who underwent a prostate biopsy. From among that population, we identified patients who underwent a unilateral or bilateral hernia repair after either RP or EBRT. Kaplan-Meier plots showed IH repair-free survival rates. Univariable and multivariable Cox regression models tested the predictors of IH repair after RP or EBRT. Covariates consisted of age, year of surgery, and Charlson Comorbidity Index. Results: IH repair-free survival rates at 1, 2, 5, and 10 years were 96.8, 94.3, 90.5, and 86.2% vs. 98.9, 98.0, 95.4, and 92.2%, respectively, in RP vs. EBRT patients (log-rank test, p < 0.001). IH repair-free survival rates in the biopsy population were 98.3, 97.1, 94.9, and 90.2% at the same four time points. In multivariable Cox regression models, RP predisposed to a 2.3-fold higher risk of IH repair than EBRT (p < 0.001). Besides therapy type, patient age (p < 0.001) represented the only other independent predictor of IH repair. Conclusions: RP predisposes to a higher rate of IH repair relative to EBRT. This observation should be considered at informed consent.

  14. Comparing ligo merger rate observations with theory: distribution of star-forming conditions

    SciTech Connect

    Belczynski, Kryzysztof; Kopparapu, R; O' Shaughnessy, R

    2008-01-01

    Within the next decade, ground based gravitational wave detectors are in principle capable of determining the compact object merger rate per unit volume of the local universe to better than 20% with more than 30 detections. Though these measurements can constrain our models of stellar, binary, and cluster evolution in the nearby present-day and ancient universe, we argue that the universe is sufficiently heterogeneous (in age and metallicity distribution at least) and that merger rates predicted by these models can be sufficiently sensitive to those heterogeneities so that a fair comparison of models per unit similar star forming mass necessarily introduces at least an additional 30%--50% systematic error into any constraints on compact binary evolution models. Without adding new electromagnetic constraints on massive binary evolution or relying on more information from each merger (e.g. , binary masses and spins), as few as the {approx_equal}5 merger detections could exhaust the information available in a naive comparison to merger rate predictions. As a concrete example immediately relevant to analysis of initial and enhanced LIGO results, we use a nearby-universe catalog to demonstrate that no one tracer of stellar content can be consistently used to constrain merger rates without introducing a systematic error of order 0(30%) at 90% confidence (depending on the type of binary involved). For example, though binary black holes typically take many Gyr to merge, binary neutron stars often merge rapidly; different tracers of stellar content are required for these two types. More generally, we argue that theoretical binary evolution can depend sufficiently sensitively on star-forming conditions -- even assuming no uncertainty in binary evolution model -- that the distribution of star forming conditions must be incorporated to reduce the systematic error in merger rate predictions below roughly 40%. We emphasize that the degree of sensitivity to star

  15. Subtype-specific incidence rates of lymphoid malignancies in Hong Kong compared to the United States, 2001-2010.

    PubMed

    Bassig, Bryan A; Au, Wing-Yan; Mang, Oscar; Ngan, Roger; Morton, Lindsay M; Ip, Dennis K M; Hu, Wei; Zheng, Tongzhang; Seow, Wei Jie; Xu, Jun; Lan, Qing; Rothman, Nathaniel

    2016-06-01

    Clinical studies of lymphoid malignancies (LMs) have suggested that the descriptive patterns of LMs differ in East Asia compared to Western populations. However, there are very limited available data on population-based, subtype-specific incidence rates of LMs in the East Asian population, particularly in Chinese. Using data from the Hong Kong (HK) Cancer Registry and United States (U.S.) SEER Program, we calculated and compared age-adjusted incidence rates of LM subtypes in HK to those in Whites and Asians living in the U.S. Overall and sex-specific rates were calculated for the period 2001-2010. The incidence of most subtypes was low in the HK population, with rates <1 case per 100,000 for all subtypes except for diffuse large B-cell lymphoma (3.26/100,000) and plasma cell neoplasms (1.99/100,000). Age-adjusted incidence rates of all evaluated B-cell subtypes were significantly higher in U.S. Whites compared to HK, with standardized rate ratios (SRRs) ranging from 1.6 (Burkitt lymphoma) to 9.1 (chronic lymphocytic leukemia/small lymphocytic lymphoma). Rates in U.S. Asians were generally intermediate to those in U.S. Whites and HK. Conversely, rates of extranodal NK/T-cell lymphoma were significantly lower in both U.S. Whites (SRR=0.2) and U.S. Asians (SRR=0.5) compared to HK. Our data provide new insight into the subtype-specific patterns of LMs in the Chinese population, and suggest the need for etiological studies of LMs in the East Asian population to elucidate the factors responsible for these differences in the geographic incidence patterns. PMID:26991956

  16. Methods for Using Medicare Data to Compare Procedure Rates among Asians, Blacks, Hispanics, Native Americans, and Whites

    PubMed Central

    Escarce, José J; McGuire, Thomas G

    2003-01-01

    Objective Small sample sizes in Asian, Hispanic, and Native American groups and misreporting of race/ethnicity across all groups (including blacks and whites) limit the usefulness of racial/ethnic comparisons based on Medicare data. The objective of this paper is to compare procedure rates for these groups using Medicare data, to assess how small sample size and misreporting affect the validity of comparisons, and to compare rates after correcting for misreporting. Data We use 1997 physician claims data for a 5 percent sample of Medicare beneficiaries aged 65 and older to study cardiac procedures and tests. Study Design We calculate age and sex-adjusted rates and confidence intervals by race/ethnicity. Confidence intervals are compared among the groups. Out-of-sample data on misreporting of race/ethnicity are used to assess potential bias due to misreporting, and to correct for the bias. Principal Findings Sample sizes are sufficient to find significant ethnic and racial differences for most procedures studied. Blacks' rates tend to be lower than whites. Asian and Hispanic rates also tend to be lower than whites', and about the same as blacks'. Sample sizes for Native Americans are very small (about .1 percent of the data); nonetheless, some significant differences from whites can still be identified. Biases in rates due to misreporting are small (less than 10 percent) for blacks, Hispanics, and whites. Biases in rates for Asians and Native Americans are greater, and exceed 20 percent for some procedures. Conclusions Sample sizes for Asians, blacks, and Hispanics are generally adequate to permit meaningful comparisons with whites. Implementing a correction for misreporting makes Medicare data useful for all ethnic groups. Misreporting race/ethnicity and small sample sizes do not materially limit the usefulness of Medicare data for comparing rates among racial and ethnic groups. PMID:14596392

  17. Meerwein-Ponndorf-Verley alkynylation of aldehydes: essential modification of aluminium alkoxides for rate acceleration and asymmetric synthesis.

    PubMed

    Ooi, Takashi; Miura, Tomoya; Ohmatsu, Kohsuke; Saito, Akira; Maruoka, Keiji

    2004-11-21

    A novel carbonyl alkynylation has been accomplished based on utilization of the Meerwein-Ponndorf-Verley (MPV) reaction system. The success of the MPV alkynylation crucially depends on the discovery of the remarkable ligand acceleration effect of 2,2'-biphenol. For example, the alkynylation of chloral (2c) with the aluminium alkoxide 6(R = Ph), prepared in situ from Me(3)Al, 2,2'-biphenol and 2-methyl-4-phenyl-3-butyn-2-ol (1a) as an alkynyl source, proceeded smoothly in CH(2)Cl(2) at room temperature to give the desired propargyl alcohol 3ca in almost quantitative yield after 5 h stirring. The characteristic feature of this new transformation involving no metal alkynides can be visualized by the fact that the alkynyl group bearing keto carbonyl was transferred successfully to aldehyde carbonyl without any side reactions on keto carbonyl. Although the use of (S)-1,1[prime or minute]-bi-2-naphthol and its simple analogues was found to be unsuitable for inducing asymmetry in this reaction, design of new chiral biphenols bearing a certain flexibility of the biphenyl axis led to satisfactory results in terms of enantioselectivity as well as reactivity. PMID:15534709

  18. GroEL/ES Chaperonin Modulates the Mechanism and Accelerates the Rate of TIM-Barrel Domain Folding

    PubMed Central

    Bracher, Andreas; Engen, John R.; Hayer-Hartl, Manajit; Hartl, F. Ulrich

    2014-01-01

    SUMMARY The GroEL/ES chaperonin system functions as a protein folding cage. Many obligate substrates of GroEL share the (βα)8 TIM-barrel fold, but how the chaperonin promotes folding of these proteins is not known. Here we analyzed the folding of DapA at peptide resolution using hydrogen/deuterium exchange and mass spectrometry. During spontaneous folding, all elements of the DapA TIM-barrel acquire structure simultaneously, in a process associated with a long search time. In contrast, GroEL/ES accelerates folding more than 30-fold by catalyzing segmental structure formation in the TIM-barrel. Segmental structure formation is also observed during the fast spontaneous folding of a structural homolog of DapA from a bacterium that lacks GroEL/ES. Thus, chaperonin-independence correlates with folding properties otherwise enforced by protein confinement in the GroEL/ES cage. We suggest that folding catalysis by GroEL/ES is required by a set of proteins to reach native state at a biologically relevant time-scale, avoiding aggregation or degradation. PMID:24813614

  19. Comparing quantum versus Markov random walk models of judgements measured by rating scales

    PubMed Central

    Wang, Z.; Busemeyer, J. R.

    2016-01-01

    Quantum and Markov random walk models are proposed for describing how people evaluate stimuli using rating scales. To empirically test these competing models, we conducted an experiment in which participants judged the effectiveness of public health service announcements from either their own personal perspective or from the perspective of another person. The order of the self versus other judgements was manipulated, which produced significant sequential effects. The quantum and Markov models were fitted to the data using the same number of parameters, and the model comparison strongly supported the quantum over the Markov model. PMID:26621984

  20. Doubling Graduation Rates: Three-Year Effects of CUNY's Accelerated Study in Associate Programs (ASAP) for Developmental Education Students

    ERIC Educational Resources Information Center

    Scrivener, Susan; Weiss, Michael J.; Ratledge, Alyssa; Rudd, Timothy; Sommo, Colleen; Fresques, Hannah

    2015-01-01

    Community colleges offer a pathway to the middle class for low-income individuals. Although access to college has expanded, graduation rates at community colleges remain low, especially for students who need developmental (remedial) courses to build their math, reading, or writing skills. The City University of New York's (CUNY's) Accelerated…

  1. Comparative analyses of evolutionary rates reveal different pathways to encephalization in bats, carnivorans, and primates

    PubMed Central

    Smaers, Jeroen B.; Dechmann, Dina K. N.; Goswami, Anjali; Soligo, Christophe; Safi, Kamran

    2012-01-01

    Variation in relative brain size is commonly interpreted as the result of selection on neuronal capacity. However, this approach ignores that relative brain size is also linked to another highly adaptive variable: body size. Considering that one-way tradeoff mechanisms are unlikely to provide satisfactory evolutionary explanations, we introduce an analytical framework that describes and quantifies all possible evolutionary scenarios between two traits. To investigate the effects of body mass changes on the interpretation of relative brain size evolution, we analyze three mammalian orders that are expected to be subject to different selective pressures on body size due to differences in locomotor adaptation: bats (powered flight), primates (primarily arboreal), and carnivorans (primarily terrestrial). We quantify rates of brain and body mass changes along individual branches of phylogenetic trees using an adaptive peak model of evolution. We find that the magnitude and variance of the level of integration of brain and body mass rates, and the subsequent relative influence of either brain or body size evolution on the brain–body relationship, differ significantly between orders and subgroups within orders. Importantly, we find that variation in brain–body relationships was driven primarily by variability in body mass. Our approach allows a more detailed interpretation of correlated trait evolution and variation in the underlying evolutionary pathways. Results demonstrate that a principal focus on interpreting relative brain size evolution as selection on neuronal capacity confounds the effects of body mass changes, thereby hiding important aspects that may contribute to explaining animal diversity. PMID:23071335

  2. Factors Associated With Chest Wall Toxicity After Accelerated Partial Breast Irradiation Using High-Dose-Rate Brachytherapy

    SciTech Connect

    Brown, Sheree; Vicini, Frank; Vanapalli, Jyotsna R.; Whitaker, Thomas J.; Pope, D. Keith; Lyden, Maureen; Bruggeman, Lisa; Haile, Kenneth L.; McLaughlin, Mark P.

    2012-07-01

    Purpose: The purpose of this analysis was to evaluate dose-volume relationships associated with a higher probability for developing chest wall toxicity (pain) after accelerated partial breast irradiation (APBI) by using both single-lumen and multilumen brachytherapy. Methods and Materials: Rib dose data were available for 89 patients treated with APBI and were correlated with the development of chest wall/rib pain at any point after treatment. Ribs were contoured on computed tomography planning scans, and rib dose-volume histograms (DVH) along with histograms for other structures were constructed. Rib DVH data for all patients were sampled at all volumes {>=}0.008 cubic centimeter (cc) (for maximum dose related to pain) and at volumes of 0.5, 1, 2, and 3 cc for analysis. Rib pain was evaluated at each follow-up visit. Patient responses were marked as yes or no. No attempt was made to grade responses. Eighty-nine responses were available for this analysis. Results: Nineteen patients (21.3%) complained of transient chest wall/rib pain at any point in follow-up. Analysis showed a direct correlation between total dose received and volume of rib irradiated with the probability of developing rib/chest wall pain at any point after follow-up. The median maximum dose at volumes {>=}0.008 cc of rib in patients who experienced chest wall pain was 132% of the prescribed dose versus 95% of the prescribed dose in those patients who did not experience pain (p = 0.0035). Conclusions: Although the incidence of chest wall/rib pain is quite low with APBI brachytherapy, attempts should be made to keep the volume of rib irradiated at a minimum and the maximum dose received by the chest wall as low as reasonably achievable.

  3. Comparative survey of potential nitrate and sulfate reduction rates in aquatic sediments

    NASA Astrophysics Data System (ADS)

    Laverman, Anniet M.; Pallud, Céline; Abell, Jeffrey; Cappellen, Philippe Van

    2012-01-01

    Nitrate and sulfate are two major terminal electron acceptors of anaerobic respiration in nearshore sediments. Potential nitrate and sulfate reduction rates (NRR and SRR) were determined on surficial sediments sampled at 14 sites representing a wide range of shallow-water depositional environments. The rates were obtained by supplying undisturbed slices of sediments with nitrate, sulfate or both using a flow-through reactor technique. No external electron donor was added to the sediments. The results indicate that all studied sediments harbored viable and coexisting nitrate- and sulfate-reducing communities, which were able to instantaneously consume the electron acceptors supplied to the reactors. On average, NRR exceeded SRR by about one order of magnitude (309 ± 180 nmol NO3- cm-3 h-1versus 37 ± 29 nmol SO42- cm-3 h-1). The NRR:SRR molar ratio, however, varied significantly from site to site, with values ranging from 1.7 to 59. Nitrite production, indicative of incomplete nitrate reduction, was observed in all studied sediments and, on average, accounted for 45% of NRR (range 3-80%). Production of sulfate under nitrate-reducing conditions was observed in 10 out of 14 of the studied sediments, suggesting a common occurrence of sulfide oxidation coupled to nitrate reduction. Oxidation of sulfide accounted for 0 to 40% of NRR in the nitrate-only experiments. When both electron acceptors were supplied simultaneously, net sulfate consumption decreased on average by 45%. The effect of nitrate on SRR was highly variable, however, ranging from near complete inhibition to a 25% enhancement of SRR. Overall, the results of this study point to the need to critically reassess the model formulations used to represent anaerobic respiration processes and their interactions in early diagenetic models.

  4. Accelerated Partial Breast Irradiation With Low-Dose-Rate Interstitial Implant Brachytherapy After Wide Local Excision: 12-Year Outcomes From a Prospective Trial

    SciTech Connect

    Hattangadi, Jona A.; Powell, Simon N.; MacDonald, Shannon M.; Mauceri, Thomas; Ancukiewicz, Marek; Freer, Phoebe; Lawenda, Brian; Alm El-Din, Mohamed A.; Gadd, Michele A.; Smith, Barbara L.; Taghian, Alphonse G.

    2012-07-01

    Purpose: To evaluate the long-term toxicity, cosmesis, and local control of accelerated partial breast irradiation with implant brachytherapy after wide local excision for Stage T1N0 breast cancer (BCa). Materials and Methods: Between 1997 and 2001, 50 patients with Stage T1N0M0 BCa were treated in a Phase I-II protocol using low-dose-rate accelerated partial breast irradiation with implant brachytherapy after wide local excision and lymph node surgery. The total dose was escalated in three groups: 50 Gy (n = 20), 55 Gy (n = 17), and 60 Gy (n = 13). Patient- and physician-assessed breast cosmesis, patient satisfaction, toxicity, mammographic abnormalities, repeat biopsies, and disease status were prospectively evaluated at each visit. Kendall's tau ({tau}{sub {beta}}) and logistic regression analyses were used to correlate outcomes with dose, implant volume, patient age, and systemic therapy. Results: The median follow-up period was 11.2 years (range, 4-14). The patient satisfaction rate was 67%, 67% reported good-excellent cosmesis, and 54% had moderate-severe fibrosis. Higher dose was correlated with worse cosmetic outcome ({tau}{sub {beta}} 0.6, p < .0001), lower patient satisfaction ({tau}{sub {beta}} 0.5, p < .001), and worse fibrosis ({tau}{sub {beta}} 0.4, p = .0024). Of the 50 patients, 35% had fat necrosis and 34% developed telangiectasias {>=}1 cm{sup 2}. Grade 3-4 late skin and subcutaneous toxicities were seen in 4 patients (9%) and 6 patients (13%), respectively, and both correlated with higher dose ({tau}{sub {beta}} 0.3-0.5, p {<=} .01). One patient had Grade 4 skin ulceration and fat necrosis requiring surgery. Mammographic abnormalities were seen in 32% of the patients, and 30% underwent repeat biopsy, of which 73% were benign. Six patients had ipsilateral breast recurrence: five elsewhere in the breast, and one at the implant site. One patient died of metastatic BCa after recurrence. The 12-year actuarial local control, recurrence-free survival

  5. Homocysteine-Lowering by B Vitamins Slows the Rate of Accelerated Brain Atrophy in Mild Cognitive Impairment: A Randomized Controlled Trial

    PubMed Central

    Smith, Stephen M.; de Jager, Celeste A.; Whitbread, Philippa; Johnston, Carole; Agacinski, Grzegorz; Oulhaj, Abderrahim; Bradley, Kevin M.; Jacoby, Robin

    2010-01-01

    Background An increased rate of brain atrophy is often observed in older subjects, in particular those who suffer from cognitive decline. Homocysteine is a risk factor for brain atrophy, cognitive impairment and dementia. Plasma concentrations of homocysteine can be lowered by dietary administration of B vitamins. Objective To determine whether supplementation with B vitamins that lower levels of plasma total homocysteine can slow the rate of brain atrophy in subjects with mild cognitive impairment in a randomised controlled trial (VITACOG, ISRCTN 94410159). Methods and Findings Single-center, randomized, double-blind controlled trial of high-dose folic acid, vitamins B6 and B12 in 271 individuals (of 646 screened) over 70 y old with mild cognitive impairment. A subset (187) volunteered to have cranial MRI scans at the start and finish of the study. Participants were randomly assigned to two groups of equal size, one treated with folic acid (0.8 mg/d), vitamin B12 (0.5 mg/d) and vitamin B6 (20 mg/d), the other with placebo; treatment was for 24 months. The main outcome measure was the change in the rate of atrophy of the whole brain assessed by serial volumetric MRI scans. Results A total of 168 participants (85 in active treatment group; 83 receiving placebo) completed the MRI section of the trial. The mean rate of brain atrophy per year was 0.76% [95% CI, 0.63–0.90] in the active treatment group and 1.08% [0.94–1.22] in the placebo group (P = 0.001). The treatment response was related to baseline homocysteine levels: the rate of atrophy in participants with homocysteine >13 µmol/L was 53% lower in the active treatment group (P = 0.001). A greater rate of atrophy was associated with a lower final cognitive test scores. There was no difference in serious adverse events according to treatment category. Conclusions and Significance The accelerated rate of brain atrophy in elderly with mild cognitive impairment can be slowed by treatment with homocysteine

  6. Comparing the Use of Global Rating Scale with Checklists for the Assessment of Central Venous Catheterization Skills Using Simulation

    ERIC Educational Resources Information Center

    Ma, Irene W. Y.; Zalunardo, Nadia; Pachev, George; Beran, Tanya; Brown, Melanie; Hatala, Rose; McLaughlin, Kevin

    2012-01-01

    The use of checklists is recommended for the assessment of competency in central venous catheterization (CVC) insertion. To explore the use of a global rating scale in the assessment of CVC skills, this study seeks to compare its use with two checklists, within the context of a formative examination using simulation. Video-recorded performances of…

  7. Learning Rates and Known-to-Unknown Flash-Card Ratios: Comparing Effectiveness While Holding Instructional Time Constant

    ERIC Educational Resources Information Center

    Forbes, Bethany E.; Skinner, Christopher H.; Black, Michelle P.; Yaw, Jared; Booher, Joshua; Delisle, Jean

    2013-01-01

    Using alternating treatments designs, we compared learning rates across 2 computer-based flash-card interventions (3?min each): a traditional drill intervention with 15 unknown words and an interspersal intervention with 12 known words and 3 unknown words. Each student acquired more words under the traditional drill intervention. Discussion…

  8. Implementation of Constant Dose Rate and Constant Angular Spacing Intensity-modulated Arc Therapy for Cervical Cancer by Using a Conventional Linear Accelerator

    PubMed Central

    Zhang, Ruo-Hui; Fan, Xiao-Mei; Bai, Wen-Wen; Cao, Yan-Kun

    2016-01-01

    Background: Volumetric-modulated arc therapy (VMAT) can only be implemented on the new generation linacs such as the Varian Trilogy® and Elekta Synergy®. This prevents most existing linacs from delivering VMAT. The purpose of this study was to investigate the feasibility of using a conventional linear accelerator delivering constant dose rate and constant angular spacing intensity-modulated arc therapy (CDR-CAS-IMAT) for treating cervical cancer. Methods: Twenty patients with cervical cancer previously treated with intensity-modulated radiation therapy (IMRT) using Varian Clinical 23EX were retreated using CDR-CAS-IMAT. The planning target volume (PTV) was set as 50.4 Gy in 28 fractions. Plans were evaluated based on the ability to meet the dose volume histogram. The homogeneity index (HI), target volume conformity index (CI), the dose to organs at risk, radiation delivery time, and monitor units (MUs) were also compared. The paired t-test was used to analyze the two data sets. All statistical analyses were performed using SPSS 19.0 software. Results: Compared to the IMRT group, the CDR-CAS-IMAT group showed better PTV CI (0.85 ± 0.03 vs. 0.81 ± 0.03, P = 0.001), clinical target volume CI (0.46 ± 0.05 vs. 0.43 ± 0.05, P = 0.001), HI (0.09±0.02 vs. 0.11 ± 0.02, P = 0.005) and D95 (5196.33 ± 28.24 cGy vs. 5162.63 ± 31.12 cGy, P = 0.000), and cord D2 (3743.8 ± 118.7 cGy vs. 3806.2 ± 98.7 cGy, P = 0.017) and rectum V40 (41.9 ± 6.1% vs. 44.2 ± 4.8%, P = 0.026). Treatment time (422.7 ± 46.7 s vs. 84.6 ± 7.8 s, P = 0.000) and the total plan Mus (927.4 ± 79.1 vs. 787.5 ± 78.5, P = 0.000) decreased by a factor of 0.8 and 0.15, respectively. The IMRT group plans were superior to the CDR-CAS-IMAT group plans considering decreasing bladder V50 (17.4 ± 4.5% vs. 16.6 ± 4.2%, P = 0.049), bowel V30 (39.6 ± 6.5% vs. 36.6 ± 7.5%, P = 0.008), and low-dose irradiation volume; there were no significant differences in other statistical indexes. Conclusions

  9. Probing neutrino mass hierarchy by comparing the charged-current and neutral-current interaction rates of supernova neutrinos

    NASA Astrophysics Data System (ADS)

    Lai, Kwang-Chang; Lee, Fei-Fan; Lee, Feng-Shiuh; Lin, Guey-Lin; Liu, Tsung-Che; Yang, Yi

    2016-07-01

    The neutrino mass hierarchy is one of the neutrino fundamental properties yet to be determined. We introduce a method to determine neutrino mass hierarchy by comparing the interaction rate of neutral current (NC) interactions, ν(bar nu) + p → ν(bar nu) + p, and inverse beta decays (IBD), bar nue + p → n + e+, of supernova neutrinos in scintillation detectors. Neutrino flavor conversions inside the supernova are sensitive to neutrino mass hierarchy. Due to Mikheyev-Smirnov-Wolfenstein effects, the full swapping of bar nue flux with the bar nux (x = μ, τ) one occurs in the inverted hierarchy, while such a swapping does not occur in the normal hierarchy. As a result, more high energy IBD events occur in the detector for the inverted hierarchy than the high energy IBD events in the normal hierarchy. By comparing IBD interaction rate with the mass hierarchy independent NC interaction rate, one can determine the neutrino mass hierarchy.

  10. Comparative study on chemical pretreatments to accelerate enzymatic hydrolysis of aquatic macrophyte biomass used in water purification processes.

    PubMed

    Mishima, D; Tateda, M; Ike, M; Fujita, M

    2006-11-01

    In this study, enzymatic hydrolysis of two floating aquatic plants which are suitable for water purification, water hyacinth (Eichhornia crassipes) and water lettuce (Pistia stratiotes L.), was performed to produce sugars. Twenty chemical pretreatments were comparatively examined in order to improve the efficiency of enzymatic hydrolysis. As a result, the alkaline/oxidative (A/O) pretreatment, in which sodium hydroxide and hydrogen peroxide were used, was the most effective pretreatment in terms of improving enzymatic hydrolysis of the leaves of water hyacinth and water lettuce. The amount of reducing sugars in enzymatic hydrolysate of water lettuce leaves was 1.8 times higher than that of water hyacinth leaves, therefore water lettuce seems to be more attractive as a biomass resource than water hyacinth. Although roots of these plants contained large amounts of polysaccharides such as cellulose and hemicellulose, they generated less monosaccharides than from leaves, no matter which chemical pretreatment was tested. PMID:16309902

  11. Comparative Evaluation of Crystalloid Resuscitation Rate in a Human Model of Compensated Haemorrhagic Shock

    PubMed Central

    Ho, Loretta; Lau, Lawrence; Churilov, Leonid; Riedel, Bernhard; McNicol, Larry; Hahn, Robert G.; Weinberg, Laurence

    2016-01-01

    ABSTRACT Introduction: The most effective rate of fluid resuscitation in haemorrhagic shock is unknown. Methods: We performed a randomized crossover pilot study in a healthy volunteer model of compensated haemorrhagic shock. Following venesection of 15 mL/kg of blood, participants were randomized to 20 mL/kg of crystalloid over 10 min (FAST treatment) or 30 min (SLOW treatment). The primary end point was oxygen delivery (DO2). Secondary end points included pressure and flow-based haemodynamic variables, blood volume expansion, and clinical biochemistry. Results: Nine normotensive healthy adult volunteers participated. No significant differences were observed in DO2 and biochemical variables between the SLOW and FAST groups. Blood volume was reduced by 16% following venesection, with a corresponding 5% reduction in cardiac index (CI) (P < 0.001). Immediately following resuscitation the increase in blood volume corresponded to 54% of the infused volume under FAST treatment and 69% of the infused volume under SLOW treatment (P = 0.03). This blood volume expansion attenuated with time to 24% and 25% of the infused volume 30 min postinfusion. During fluid resuscitation, blood pressure was higher under FAST treatment. However, CI paradoxically decreased in most participants during the resuscitation phase; a finding not observed under SLOW treatment. Conclusion: FAST or SLOW fluid resuscitation had no significant impact on DO2 between treatment groups. In both groups, changes in CI and blood pressure did not reflect the magnitude of intravascular blood volume deficit. Crystalloid resuscitation expanded intravascular blood volume by approximately 25%. PMID:26974423

  12. Acceleration of the Fe(III)EDTA(-) reduction rate in BioDeNO(x) reactors by dosing electron mediating compounds.

    PubMed

    Maas, Peter van der; Brink, Paula van den; Klapwijk, Bram; Lens, Piet

    2009-04-01

    BioDeNO(x), a novel technique to remove NO(x) from industrial flue gases, is based on absorption of gaseous nitric oxide into an aqueous Fe(II)EDTA(2-) solution, followed by the biological reduction of Fe(II)EDTA(2-) complexed NO to N(2). Besides NO reduction, high rate biological Fe(III)EDTA(-) reduction is a crucial factor for a succesful application of the BioDeNO(x) technology, as it determines the Fe(II)EDTA(2-) concentration in the scrubber liquor and thus the efficiency of NO removal from the gas phase. This paper investigates the mechanism and kinetics of biological Fe(III)EDTA(-) reduction by unadapted anaerobic methanogenic sludge and BioDeNO(x) reactor mixed liquor. The influence of different electron donors, electron mediating compounds and CaSO(3) on the Fe(III)EDTA(-) reduction rate was determined in batch experiments (21mM Fe(III)EDTA(-), 55 degrees C, pH 7.2+/-0.2). The Fe(III)EDTA(-) reduction rate depended on the type of electron donor, the highest rate (13.9mMh(-1)) was observed with glucose, followed by ethanol, acetate and hydrogen. Fe(III)EDTA(-) reduction occurred at a relatively slow (4.1mMh(-1)) rate with methanol as the electron donor. Small amounts (0.5mM) of sulfide, cysteine or elemental sulfur accelerated the Fe(III)EDTA(-) reduction. The amount of iron reduced significantly exceeded the amount that can be formed by the chemical reaction of sulfide with Fe(III)EDTA(-), suggesting that the Fe(III)EDTA(-) reduction was accelerated via an auto-catalytic process with an unidentified electron mediating compound, presumably polysulfides, formed out of the sulfur additives. Using ethanol as electron donor, the specific Fe(III)EDTA(-) reduction rate was linearly related to the amount of sulfide supplied. CaSO(3) (0.5-100mM) inhibited Fe(III)EDTA(-) reduction, probably because SO(3)(2-) scavenged the electron mediating compound. PMID:18561978

  13. Rates of Cancers and Opportunistic Infections in Patients With Psoriatic Arthritis Compared With Patients Without Psoriatic Arthritis

    PubMed Central

    Hagberg, Katrina Wilcox; Li, Lin; Peng, Michael; Paris, Maria; Shah, Kamal; Jick, Susan S.

    2016-01-01

    Objectives This study aimed to estimate rates of cancer or opportunistic infection in patients with psoriatic arthritis (PsA) compared with patients without PsA. Methods Using the Clinical Practice Research Datalink, we conducted a cohort study of patients with a PsA diagnosis and patients without such diagnosis, matched on age, sex, general practice, and calendar time, to assess the incidence of cancers (solid, hematologic, and nonmelanoma skin cancer) and opportunistic infections. We estimated incidence rates (IRs) and IR ratios (IRRs) with 95% confidence intervals (CIs) for each outcome and stratified results in the PsA cohort by receipt of systemic PsA drugs. Results The rate of hematologic cancer was slightly higher in the PsA cohort compared with the non-PsA cohort (IRR, 1.52; 95% CI, 1.10–2.10), whereas the rates of solid cancer and of nonmelanoma skin cancer were similar between the PsA and non-PsA cohorts (IRR, 1.01; 95% CI, 0.90–1.13; and IRR, 0.97; 95% CI, 0.82–1.14, respectively). Incidence rates were higher for PsA patients who received prescriptions for PsA drugs compared with those who did not. The IRs for infection were higher in the PsA compared with the non-PsA cohort (IRR, 1.39; 95% CI, 1.31–1.47) and were significantly higher in patients who received prescriptions (IRR, 1.71; 95% CI, 1.52–1.91). Conclusions The rates of solid and nonmelanoma skin cancers were similar in patients with PsA compared with patients without PsA, but the rates of hematologic cancer and opportunistic infections were higher in patients with PsA. In patients with PsA, rates of all outcomes were higher among those who received prescriptions for systemic PsA therapy. PMID:26886439

  14. In vitro O 2 fluxes compared with 14C production and other rate terms during the JGOFS Equatorial Pacific experiment

    NASA Astrophysics Data System (ADS)

    Bender, Michael; Orchardo, Joe; Dickson, Mary-Lynn; Barber, Richard; Lindley, Steven

    1999-04-01

    We report rates of gross and net O 2 production measured in vitro during JGOFS cruises in the equatorial Pacific in spring and fall, 1992. We scale O 2 productivities to net and gross C production. We then compare the calculated rates with 14C production and with new/export production measured by various techniques. 14C productivities in samples incubated for 24 h are about 45% of gross carbon production rates calculated from gross O 2 production. The difference is compatible with expected rates of the Mehler reaction, photorespiration, excretion, and community mitochondrial respiration. 14C production rates are similar to net carbon production rates in the upper half of the euphotic zone. At lower irradiances, where net C production can be zero or less, 14C productivities lie between net community production and gross primary production. Net carbon production rates in vitro are a factor of =4-20 times greater than estimates from drifting sediment trap and tracer transport studies. This difference probably reflects anomalous accumulation of POC in bottles because of the exclusion of grazers.

  15. Accelerated Stem Growth Rates and Improved Fiber Properties of Loblolly Pine: Functional Analysis Of CyclinD from Pinus taeda

    SciTech Connect

    Dr. John Cairney, School of Biology and Institute of Paper Science and Technology @ Georgia Tech, Georgia Institute of Technology; Dr. Gary Peter, University of Florida; Dr. Ulrika Egertsdotter, Dept. of Forestry, Virgina Tech; Dr. Armin Wagner, New Zealand Forest Research Institute Ltd.

    2005-11-30

    A sustained supply of low-cost, high quality raw materials is essential for the future success of the U.S. forest products industry. To maximize stem (trunk) growth, a fundamental understanding of the molecular mechanisms that regulate cell divisions within the cambial meristem is essential. We hypothesize that auxin levels within the cambial meristem regulate cyclin gene expression and this in turn controls cell cycle progression as occurs in all eukaryotic cells. Work with model plant species has shown that ectopic overexpression of cyclins promotes cell division thereby increasing root growth > five times. We intended to test whether ectopic overexpression of cambial cyclins in the cambial zone of loblolly pine also promotes cell division rates that enhance stem growth rates. Results generated in model annual angiosperm systems cannot be reliably extrapolated to perennial gymnosperms, thus while the generation and development of transgenic pine is time consuming, this is the necessary approach for meaningful data. We succeeded in isolating a cyclin D gene and Clustal analysis to the Arabidopsis cyclin D gene family indicates that it is more closely related to cyclin D2 than D1 or D3 Using this gene as a probe we observed a small stimulation of cyclin D expression in somatic embryo culture upon addition of auxin. We hypothesized that trees with more cells in the vascular cambial and expansion zones will have higher cyclin mRNA levels. We demonstrated that in trees under compressive stress where the rates of cambial divisions are increased on the underside of the stem relative to the top or opposite side, there was a 20 fold increase in the level of PtcyclinD1 mRNA on the compressed side of the stem relative to the opposite. This suggests that higher secondary growth rates correlate with PtcyclinD1 expression. We showed that larger diameter trees show more growth during each year and that the increased growth in loblolly pine trees correlates with more cell

  16. Comparison of lower body strength, power, acceleration, speed, agility, and sprint momentum to describe and compare playing rank among professional rugby league players.

    PubMed

    Baker, Daniel G; Newton, Robert U

    2008-01-01

    Success in rugby league football seems heavily reliant on players possessing an adequate degree of various physical fitness qualities, such as strength, power, speed, agility, and endurance, as well as the individual skills and team tactical abilities. The purpose of this study was to describe and compare the lower body strength, power, acceleration, maximal speed, agility, and sprint momentum of elite first-division national rugby league (NRL) players (n = 20) to second-division state league (SRL) players (n = 20) players from the same club. Strength and maximal power were the best discriminators of which players were in the NRL or SRL squads. None of the sprinting tests, such as acceleration (10-m sprint), maximal speed (40-m sprint), or a unique 40-m agility test, could distinguish between the NRL or SRL squads. However, sprint momentum, which was a product of 10-m velocity and body mass, was better for discriminating between NRL and SRL players as heavier, faster players would possess better drive forward and conversely be better able to repel their opponents' drive forward. Strength and conditioning specialists should therefore pay particular attention to increasing lower body strength and power and total body mass through appropriate resistance training while maintaining or improving 10-m sprint speed to provide their players with the underlying performance characteristics of play at the elite level in rugby leagues. PMID:18296969

  17. Unsatisfactory rate in liquid-based cervical samples as compared to conventional smears: A study from tertiary care hospital

    PubMed Central

    Gupta, Nalini; Bhar, Vikrant S.; Rajwanshi, Arvind; Suri, Vanita

    2016-01-01

    Background: Developed countries adopted liquid-based cytology (LBC) cervical cytology, partly because of its lower proportions of unsatisfactory (U/S)/inadequate samples. This study was carried out to evaluate effect on the rate of U/S samples after introduction of LBC in our laboratory. Materials and Methods: An audit of U/S cervical samples was performed, which included split samples (n = 1000), only conventional Pap smear (CPS) smears (n = 1000), and only LBC samples (n = 1000). The smears were reviewed by two observers independently, and adequacy for the samples was assessed as per The Bethesda System 2001. The reasons for U/S rate in split samples were categorized into various cytologic and/or technical reasons. Results: U/S rate was far less in only LBC samples (1.2%) as compared to only CPS (10.5%) cases. Cases in the satisfactory but limited category were also less in only LBC (0.4%) as compared to only CPS (3.2%) samples. The main reasons for U/S smears in split samples were low cell count (37.2% in CPS; 58.8% in LBC). The second main reason was low cellularity with excess blood and only excess blood in CPS samples. Conclusion: There was a significant reduction of U/S rate in LBC samples as compared to CPS samples, and the difference was statistically significant. The main cause of U/S samples in LBC was low cellularity indicating a technical fault in sample collection. The main cause of U/S rate in CPS was low cellularity followed by low cellularity with excess blood. Adequate training of sample takers and cytologists for the precise cell count to determine adequacy in smears can be of great help in reducing U/S rate. PMID:27382408

  18. Linear Accelerators

    NASA Astrophysics Data System (ADS)

    Sidorin, Anatoly

    2010-01-01

    In linear accelerators the particles are accelerated by either electrostatic fields or oscillating Radio Frequency (RF) fields. Accordingly the linear accelerators are divided in three large groups: electrostatic, induction and RF accelerators. Overview of the different types of accelerators is given. Stability of longitudinal and transverse motion in the RF linear accelerators is briefly discussed. The methods of beam focusing in linacs are described.

  19. Linear Accelerators

    SciTech Connect

    Sidorin, Anatoly

    2010-01-05

    In linear accelerators the particles are accelerated by either electrostatic fields or oscillating Radio Frequency (RF) fields. Accordingly the linear accelerators are divided in three large groups: electrostatic, induction and RF accelerators. Overview of the different types of accelerators is given. Stability of longitudinal and transverse motion in the RF linear accelerators is briefly discussed. The methods of beam focusing in linacs are described.

  20. Accelerated Rates of Nitrogen Cycling and N2O Production in Salt Marsh Sediments due to Long-Term Fertilization

    NASA Astrophysics Data System (ADS)

    Peng, X.; Ji, Q.; Angell, J.; Kearns, P.; Bowen, J. L.; Ward, B. B.

    2014-12-01

    Intensified sedimentary production of nitrous oxide (N2O), one of the most potent greenhouse gases, is one of the many possible environmental consequences of elevated nitrogen (N) loading into estuarine ecosystems. This study investigates the response to over 40 years of fertilization of nitrogen removal processes in the sediments of the Great Sippewissett Marsh in Falmouth, MA. Sediment slurries were incubated (1.5 hr) with trace amounts (< 10% of ambient concentration) of 15NH4+ + 14NO3- or 15NO3- + 14NH4+. An additional parallel incubation with 15NH4+ + 14NO3- and 1 mM of allylthiourea (ATU) was included to measure rates of anaerobic ammonia oxidation (anammox). Well-homogenized slurries filled about 10% of the volume in the gas-tight incubation vials, and the rest of the volume was replaced with an O2/He (20%/80%) mixture. The production of 29N2, 44N2O and 45N2O were determined using isotope ratio mass spectrometry. The rate of total N2O production in fertilized sediments (0.89 nmol hr-1 g-1 wet weight) was 30-fold higher than in unfertilized sediments. The ratio of N2O to N2 production was also significantly higher in fertilized sediments (2.9%) than in unfertilized sediments (1.2%). This highlights the disproportionally large effect of long-term fertilization on N2O production in salt marsh sediments. The reduced oxygen level and higher ammonium concentrations in situ probably contributed to the significant rise in N2O production as a result of long-term fertilization. When detected, anammox and coupled nitrification-denitrification accounted for 10% and 14% of the total N2 production in fertilized sediments (30.5 nmol hr-1 g-1 wet weight), respectively, whereas neither was detected in unfertilized sediments. Thus these experiments indicate that N loading has important effects on multiple N cycle processes that result in N loss and N2O production.

  1. On the nature of rate acceleration in the synthesis and fragmentation of triazolines by Brønsted acid: secondary catalysis by water (hydronium triflate).

    PubMed

    Hong, Ki Bum; Donahue, Matthew G; Johnston, Jeffrey N

    2008-02-20

    Rate acceleration of the addition of benzyl azide to an electron deficient olefin is characterized using in situ IR spectroscopy. Under strictly anhydrous conditions and at depressed temperature (-20 degrees C), a triazoline intermediate is selectively formed. The stability of this protonated triazoline intermediate at -20 degrees C is indefinite, but warming of the reaction mixture to 0 degrees C or above results in its conversion to the beta-amino oxazolidine dione observed under conditions used in our earlier report. As an alternative to warming, the same conversion can be effected by the addition of a single equivalent of water. Our experiments collectively demonstrate the metastability of the protonated triazoline intermediate and secondary catalysis of triazolinium ring fragmentation by water. This behavior is attributed to the ability of water to transfer a proton from N3 to N1 of the triazoline, thereby allowing ring fragmentation and nitrogen expulsion. PMID:18217758

  2. Acceleration of runaway electrons and Joule heating in solar flares

    NASA Technical Reports Server (NTRS)

    Holman, G. D.

    1984-01-01

    The electric field acceleration of electrons out of a thermal plasma and the simultaneous Joule heating of the plasma are studied. Acceleration and heating timescales are derived and compared, and upper limits are obtained on the acceleration volume and the rate at which electrons can be accelerated. These upper limits, determined by the maximum magnetic field strength observed in flaring regions, place stringent restrictions upon the acceleration process. The role of the plasma resistivity in these processes is examined, and possible sources of anomalous resistivity are summarized. The implications of these results for the microwave and hard X-ray emission from solar flares are examined.

  3. Acceleration of runaway electrons and Joule heating in solar flares

    NASA Technical Reports Server (NTRS)

    Holman, G. D.

    1985-01-01

    The electric field acceleration of electrons out of a thermal plasma and the simultaneous Joule heating of the plasma are studied. Acceleration and heating timescales are derived and compared, and upper limits are obtained on the acceleration volume and the rate at which electrons can be accelerated. These upper limits, determined by the maximum magnetic field strength observed in flaring regions, place stringent restrictions upon the acceleration process. The role of the plasma resistivity in these processes is examined, and possible sources of anomalous resistivity are summarized. The implications of these results for the microwave and hard X-ray emission from solar flares are examined.

  4. Acceleration of the Rate-Limiting Step of Thioredoxin Folding by Replacement of its Conserved cis-Proline with (4 S)-Fluoroproline.

    PubMed

    Roderer, Daniel; Glockshuber, Rudi; Rubini, Marina

    2015-10-12

    The incorporation of the non-natural amino acids (4R)- and (4S)-fluoroproline (Flp) has been successfully used to improve protein stability, but little is known about their effect on protein folding kinetics. Here we analyzed the influence of (4R)- and (4S)-Flp on the rate-limiting trans-to-cis isomerization of the Ile75-Pro76 peptide bond in the folding of Escherichia coli thioredoxin (Trx). While (4R)-Flp at position 76 had essentially no effect on the isomerization rate in the context of the intact tertiary structure, (4S)-Flp accelerated the folding reaction ninefold. Similarly, tenfold faster trans-to-cis isomerization of Ile75-(4S)-Flp76 relative to Ile75-Pro76 was observed in the unfolded state of Trx. Our results show that the replacement of cis prolines by non-natural proline analogues can be used for modulating the folding rates of proteins with cis prolyl-peptide bonds in the native state. PMID:26382254

  5. Acceleration of positrons by a relativistic electron beam in the presence of quantum effects

    SciTech Connect

    Niknam, A. R.; Aki, H.; Khorashadizadeh, S. M.

    2013-09-15

    Using the quantum magnetohydrodynamic model and obtaining the dispersion relation of the Cherenkov and cyclotron waves, the acceleration of positrons by a relativistic electron beam is investigated. The Cherenkov and cyclotron acceleration mechanisms of positrons are compared together. It is shown that growth rate and, therefore, the acceleration of positrons can be increased in the presence of quantum effects.

  6. Comparative effects of the toxic dinoflagellate Karenia brevis on clearance rates in juveniles of four bivalve molluscs from Florida, USA.

    PubMed

    Leverone, Jay R; Shumway, Sandra E; Blake, Norman J

    2007-04-01

    The effects of Karenia brevis (Gymnodiniales, Gymnodiniaceae) on the feeding activity of juveniles of four species of bivalve mollusc were examined in the laboratory to assess the potential impacts on these important shellfish populations from Florida. Clearance rates were determined under short-term (one hour) static and long-term (two days) flow-through conditions using both whole and lysed cultures of K. brevis. Under short-term conditions, the bay scallop, Argopecten irradians, was the most sensitive species, exhibiting a 79% reduction in clearance rate at 1000 cells ml(-1) of whole K. brevis culture compared to the control (no K. brevis). The eastern oyster, Crassostrea virginica, was the least responsive, showing a 38% reduction in clearance rate between the same treatments. The green mussel, Perna viridis, and the northern quahog, Mercenaria mercenaria, displayed intermediate responses. Similar results were also observed during long-term exposures to a continuous supply of K. brevis. Bay scallops showed a significant decline in clearance rate at 100 cells ml(-1) after 24h exposure; clearance rate of oysters was not affected by K. brevis at this concentration. No mortality was observed for any species during these brief exposures. The prospect for recovery of bay scallop populations in Florida estuaries where they were once abundant may be hampered by recurring blooms of K. brevis. Reduced clearance rates in M. mercenaria at high K. brevis densities could translate into poor growth of cultured Florida hard clams. On the other hand, P. viridis, which also showed reduced clearance rates at high K. brevis concentrations, might be negatively impacted by K. brevis blooms, thereby affecting their ability to spread into estuaries hampered by recurring toxic algal blooms. PMID:17182073

  7. Thermal characterization of Li/sulfur, Li/ S-LiFePO4 and Li/S-LiV3O8 cells using Isothermal Micro-Calorimetry and Accelerating Rate Calorimetry

    NASA Astrophysics Data System (ADS)

    Seo, Jeongwook; Sankarasubramanian, Shrihari; Kim, Chi-Su; Hovington, Pierre; Prakash, Jai; Zaghib, Karim

    2015-09-01

    The thermal behavior of three cathode materials for the lithium/sulfur (Li/S) cell, namely - sulfur, sulfur-LiFePO4 (S-LFP) composite and sulfur-LiV3O8 (S-LVO) composite was studied using Isothermal Micro-Calorimetry (IMC) at various discharge rates. A continuum model was used to calculate the reversible entropic heat and irreversible resistive heat generated over the discharge process and the model data was compared to the experimental data to elucidate contributions of reversible and irreversible heats to the overall heat generated during discharge. The reaction enthalpy (ΔHRx) was measured using IMC for each elementary reaction step and in combination with the calculated reversible entropic heat and irreversible resistive heat was fitted against the experimental total heat measurement. The model showed an excellent fit against the experimental data. Further, Accelerating Rate Calorimetry (ARC) was used to study the thermal safety of these three cells. The cell with the S-LVO composite cathode was found to have the highest onset temperature for thermal runaway and also the lowest maximum self-heat rate. Results of this study suggest that S-LVO composite is a promising electrode for Li/S cells.

  8. Comparative efficacy of G6G and Ovsynch protocols on synchronization and pregnancy rate in Nili-Ravi buffalo.

    PubMed

    Waqas, M; Mehmood, M U; Shahzad, Q; Kausar, R; Sattar, A; Naseer, Z

    2016-03-01

    The aim of this work was to evaluate the efficacy of G6G and Ovsynch protocols on synchronization and pregnancy rate in Nili-Ravi buffalo. For this, a total of fifty buffalo were assigned into two treatment groups: (1) G6G (n=25) and (2) Ovsynch (n=25). The blood samples were collected from all the treated buffalo on day (D) 7 (PGF2α injection of Ovsynch) to measure the progesterone (P4). All the buffalo were fixed time inseminated (FTAI) following last GnRH of Ovsynch. Ultrasonography was performed for follicular, corpus luteum (CL) dynamics and pregnancy diagnosis. The results revealed that synchronization rate and response to final PGF2α were significantly (P<0.05) higher in G6G compared to Ovsynch. The ovulation to first GnRH of Ovsynch was higher (P<0.05) in G6G (84%) than Ovsynch (56%). The mean dominant follicle size following last GnRH of Ovsynch showed significantly larger diameter in G6G (11.7±0.2mm) compared to Ovsynch (10.9±0.2mm). Moreover, the higher (P<0.05) P4 concentration was observed in G6G than Ovsynch. The presence of double CL on D 7 was higher (P<0.05) in G6G (64%) than Ovsynch (24%) group. The pregnancy rate (P=0.08) tended to be greater in G6G compared to Ovsynch. In conclusion, G6G treatment showed better ovulatory and luteolytic response to first GnRH and PGF2α compared to Ovsynch treatment. Moreover, the addition of GnRH and PGF2α prior to Ovsynch is helpful to improve synchronization application of Ovsynch protocol in Nili-Ravi buffalo. PMID:26833275

  9. Myth Exposed: Academically Deficient Students Gain 2.3 Grade Equivalents in Only One Semester at a 96% Black Inner-City Community College in South Central Los Angeles Or Inner-City Academic Acceleration: How to Structure a Developmental Skills Program so that Black, Inner-City Students Accelerate Their Academic Growth Rate to a Rate 5.9 Times as Great as They Have Achieved in the Past.

    ERIC Educational Resources Information Center

    Wallace, Ruby; And Others

    The success of the Developmental Skills Program offered at Los Angeles Southwest College, a 96% black institution, is indicated by an average student grade equivalent gain of 2.3 years in one semester; a 5 year average accelerated academic growth rate that is 5.9 times the rate of academic growth black inner-city students have experienced in the…

  10. Can Accelerators Accelerate Learning?

    NASA Astrophysics Data System (ADS)

    Santos, A. C. F.; Fonseca, P.; Coelho, L. F. S.

    2009-03-01

    The 'Young Talented' education program developed by the Brazilian State Funding Agency (FAPERJ) [1] makes it possible for high-schools students from public high schools to perform activities in scientific laboratories. In the Atomic and Molecular Physics Laboratory at Federal University of Rio de Janeiro (UFRJ), the students are confronted with modern research tools like the 1.7 MV ion accelerator. Being a user-friendly machine, the accelerator is easily manageable by the students, who can perform simple hands-on activities, stimulating interest in physics, and getting the students close to modern laboratory techniques.

  11. PARTICLE ACCELERATOR

    DOEpatents

    Teng, L.C.

    1960-01-19

    ABS>A combination of two accelerators, a cyclotron and a ring-shaped accelerator which has a portion disposed tangentially to the cyclotron, is described. Means are provided to transfer particles from the cyclotron to the ring accelerator including a magnetic deflector within the cyclotron, a magnetic shield between the ring accelerator and the cyclotron, and a magnetic inflector within the ring accelerator.

  12. Smolt Monitoring Program Comparative Survival Rate Study (CSS); Oregon Department of Fish and Wildlife, Annual Report 2001-2002.

    SciTech Connect

    Jonasson, Brian; Carmichael, Richard

    2003-05-01

    We PIT-tagged juvenile spring chinook salmon reared at Lookingglass Hatchery in October 2001 as part of the Comparative Survival Rate Study (CSS) for migratory year (MY) 2002. We tagged 20,998 Imnaha stock spring chinook salmon, and after mortality and tag loss, we allowed the remaining 20,920 fish to leave the acclimation pond at our Imnaha River satellite facility beginning 21 March 2002 to begin their seaward migration. The fish remaining in the pond were forced out on 17 April 2002. We tagged 20,973 Catherine Creek stock captive brood progeny spring chinook salmon, and after mortality and tag loss, we allowed the remaining 20,796 fish to leave the acclimation ponds at our Catherine Creek satellite facility beginning 1 April 2001 to begin their seaward migration. The fish remaining in the ponds were forced out on 15 April 2001. We estimated survival rates, from release to Lower Granite Dam in MY 2002, for three stocks of hatchery spring chinook salmon tagged at Lookingglass Hatchery to determine their relative migration performance. Imnaha River stock and Lostine River stock survival rates were similar and were higher than the survival rate of Catherine Creek stock. We PIT-tagged 20,950 BY 2001 Imnaha River stock and 20,820 BY 2001 Catherine Creek stock captive brood progeny in October 2002 as part of the CSS for MY 2003. At the time the fish were transferred from Lookingglass Hatchery to the acclimation site, the rates of mortality and tag loss for Imnaha River stock were 0.14% and 0.06%, respectively. Catherine Creek stock, during the same period, had rates of mortality and tag loss of 0.57% and 0.31%, respectively. There was slightly elevated mortality, primarily from BKD, in one raceway of Catherine Creek stock at Lookingglass Hatchery for BY 2001.

  13. Comparing the use of global rating scale with checklists for the assessment of central venous catheterization skills using simulation.

    PubMed

    Ma, Irene W Y; Zalunardo, Nadia; Pachev, George; Beran, Tanya; Brown, Melanie; Hatala, Rose; McLaughlin, Kevin

    2012-10-01

    The use of checklists is recommended for the assessment of competency in central venous catheterization (CVC) insertion. To explore the use of a global rating scale in the assessment of CVC skills, this study seeks to compare its use with two checklists, within the context of a formative examination using simulation. Video-recorded performances of CVC insertion by 34 first-year medical residents were reviewed by two independent, trained evaluators. Each evaluator used three assessment tools: a ten-item checklist, a 21-item checklist, and a nine-item global rating scale. Exploratory principal component analysis of the global rating scale revealed two factors, accounting for 84.1% of the variance: technical ability and safety. The two checklist scores correlated positively with the weighted factor score on technical ability (0.49 [95% CI 0.17-0.71] for the 10-item checklist; 0.43 [95% CI 0.10-0.67] for the 21-item checklist) and negatively with the weighted factor score on safety (-0.17 [95% CI -0.48-0.18] for the 10-item checklist; -0.13 [95% CI -0.45-0.22] for the 21-item checklist). A checklist score of <80% was strong indication of incompetence. However, a high checklist score did not preclude incompetence. Ratings using the global rating scale identified an additional 11 candidates (32%) who were deemed incompetent despite scoring >80% on both checklists. All these candidates committed serious errors. In conclusion, the practice of universal adoption of checklists as the preferred method of assessment of procedural skills should be questioned. The inclusion of global rating scales should be considered. PMID:21877217

  14. A Comparative Study of Iron Uptake Rates and Mechanisms amongst Marine and Fresh Water Cyanobacteria: Prevalence of Reductive Iron Uptake

    PubMed Central

    Lis, Hagar; Kranzler, Chana; Keren, Nir; Shaked, Yeala

    2015-01-01

    In this contribution, we address the question of iron bioavailability to cyanobacteria by measuring Fe uptake rates and probing for a reductive uptake pathway in diverse cyanobacterial species. We examined three Fe-substrates: dissolved inorganic iron (Fe') and the Fe-siderophores Ferrioxamine B (FOB) and FeAerobactin (FeAB). In order to compare across substrates and strains, we extracted uptake rate constants (kin = uptake rate/[Fe-substrate]). Fe' was the most bioavailable Fe form to cyanobacteria, with kin values higher than those of other substrates. When accounting for surface area (SA), all strains acquired Fe' at similar rates, as their kin/SA were similar. We also observed homogeneity in the uptake of FOB among strains, but with 10,000 times lower kin/SA values than Fe'. Uniformity in kin/SA suggests similarity in the mechanism of uptake and indeed, all strains were found to employ a reductive step in the uptake of Fe' and FOB. In contrast, different uptake pathways were found for FeAB along with variations in kin/SA. Our data supports the existence of a common reductive Fe uptake pathway amongst cyanobacteria, functioning alone or in addition to siderophore-mediated uptake. Cyanobacteria combining both uptake strategies benefit from increased flexibility in accessing different Fe-substrates. PMID:25768677

  15. The crime drop in comparative perspective: the impact of the economy and imprisonment on American and European burglary rates.

    PubMed

    Rosenfeld, Richard; Messner, Steven F

    2009-09-01

    Influential statements on recent American crime reductions maintain that the crime drop was confined to the USA. Yet other research has revealed comparable crime decreases in Europe. We suggest that the USA and European crime declines occurred in tandem because they were both brought about by upturns in the economy. In light of US research showing crime reductions resulting from growth in imprisonment, we also examine the possibility that rising imprisonment rates reduced European crime rates. We test these hypotheses in a pooled cross-sectional time-series analysis of burglary rates in the USA and nine European nations between 1993 and 2006. The results indicate that burglary declines in the US and Europe were associated with rising consumer confidence. By contrast, imprisonment appears to be significantly related to burglary rates only after unusual policy interventions, such as Italy's 2006 clemency measure that dramatically reduced the size of its prison population. We interpret these findings as reflecting the structural similarity and economic integration of the world's developed nations and the uneven convergence in US and European punishment policies. PMID:19703170

  16. Acceleration schedules for a recirculating heavy-ion accelerator

    SciTech Connect

    Sharp, W.M.; Grote, D.P.

    2002-05-01

    Recent advances in solid-state switches have made it feasible to design programmable, high-repetition-rate pulsers for induction accelerators. These switches could lower the cost of recirculating induction accelerators, such as the ''small recirculator'' at Lawrence Livermore National Laboratory (LLNL), by substantially reducing the number of induction modules. Numerical work is reported here to determine what effects the use of fewer pulsers at higher voltage would have on the beam quality of the LLNL small recirculator. Lattices with different numbers of pulsers are examined using the fluid/envelope code CIRCE, and several schedules for acceleration and compression are compared for each configuration. For selected schedules, the phase-space dynamics is also studied using the particle-in-cell code WARP3d.

  17. Late Pleistocene-Holocene acceleration of uplift rate in southwest Erromango Island, Southern Vanuatu, South Pacific: relation to the growth of the Vanuatuan Mid Sedimentary Basin

    SciTech Connect

    Neef, G.; Hendy, C.

    1988-07-01

    Late Quaternary and Holocene raised coral reefs are well developed in southwestern Erromango Island, which lies in the frontal arc area of the Vanuatuan Island Arc. Eight uranium series ages and one /sup 14/C age from samples from coral reefs at three localities range in age from 4800 B.P. to about 320,000 B.P. Six of the samples dated are from the Matiwo Point area. Here the youngest reef has given a /sup 230/Th//sup 234/U age of 4800 B.P. and a slightly older reef, 4.3 m higher in elevation, has a /sup 14/C age of 5270 B.P. Inland of a cliff the youngest three of four northeastward-tilted raised reefs have given /sup 230/Th//sup 234/U ages ranging from 104,000 B.P. to about 320,000 B.P. These data indicate accelerating uplift rates for southwest Erromango: during the periods 320,000-133,000 B.P., 133,000-6000 B.P., and 6000 - 0 B.P. average uplift rates were 0.33 mm/yr, 0.65 mm/yr, and about 1 mm/yr respectively. These data are interpreted to indicate the growth of the Mid Sedimentary Basin, which lies within the frontal and volcanic arc part of the island arc complex. This increase in uplift/eastward-tilting could represent a Quaternary-Late Pleistocene increase in the subduction rate of the Australian Plate beneath Erromango.

  18. Comparative Evaluation of Frictional Properties, Load Deflection Rate and Surface Characteristics of Different Coloured TMA Archwires - An Invitro Study

    PubMed Central

    Aloysius, Arul Pradeep; Deepika; Soundararajan, Nagachandran Kandasamy; Manohar, Vijaykumar Neelam; Khan, Nayeemullah

    2015-01-01

    Introduction During tooth movement the success of sliding mechanics is dependent upon various factors which include frictional resistance at bracket-archwire interface, surface roughness of archwire materials and elastic properties of archwires. Ion implantation techniques reduce the frictional force and allow better tooth movement clinically. Aim The main objective of this study was to evaluate and compare the frictional properties, load deflection rate and surface characteristics of Honey dew and Purple coloured (Ion implanted) TMA wires with uncoated TMA wires. Materials and Methods Fifteen archwire samples were divided into three groups comprising of five samples in each group namely, Group I – Uncoated TMA wires (Control), Group II – Purple coloured TMA wires and Group III- Honey dew TMA wires. Friction and load deflection rate testing were performed with the Instron Universal testing machine and the surface characteristics of the wires were evaluated before and after sliding using Scanning Electron Microscope. Results The mean frictional characteristics and surface roughness for Honey dew TMA wires was lesser than Purple coloured TMA wires which was statistically significant. Both the coloured TMA wires showed low frictional characteristics and less surface roughness than uncoated TMA wires (the control). The mean load deflection rate was low for both coloured ion implanted TMA wires when compared to uncoated TMA wires which was statistically significant. Conclusion Coloured ion implanted TMA wires, especially Honey dew TMA wires have low friction, low load deflection rate and improved surface finish. Hence they can be used in frictionless as well as sliding mechanics, where uncoated TMA wires are inefficient. PMID:26816988

  19. Higher Rate of Tuberculosis in Second Generation Migrants Compared to Native Residents in a Metropolitan Setting in Western Europe

    PubMed Central

    Marx, Florian M.; Fiebig, Lena; Hauer, Barbara; Brodhun, Bonita; Glaser-Paschke, Gisela; Haas, Walter

    2015-01-01

    Background In Western Europe, migrants constitute an important risk group for tuberculosis, but little is known about successive generations of migrants. We aimed to characterize migration among tuberculosis cases in Berlin and to estimate annual rates of tuberculosis in two subsequent migrant generations. We hypothesized that second generation migrants born in Germany are at higher risk of tuberculosis compared to native (non-migrant) residents. Methods A prospective cross-sectional study was conducted. All tuberculosis cases reported to health authorities in Berlin between 11/2010 and 10/2011 were eligible. Interviews were conducted using a structured questionnaire including demographic data, migration history of patients and their parents, and language use. Tuberculosis rates were estimated using 2011 census data. Results Of 314 tuberculosis cases reported, 154 (49.0%) participated. Of these, 81 (52.6%) were first-, 14 (9.1%) were second generation migrants, and 59 (38.3%) were native residents. The tuberculosis rate per 100,000 individuals was 28.3 (95CI: 24.0–32.6) in first-, 10.2 (95%CI: 6.1–16.6) in second generation migrants, and 4.6 (95%CI: 3.7–5.6) in native residents. When combining information from the standard notification variables country of birth and citizenship, the sensitivity to detect second generation migration was 28.6%. Conclusions There is a higher rate of tuberculosis among second generation migrants compared to native residents in Berlin. This may be explained by presumably frequent contact and transmission within migrant populations. Second generation migration is insufficiently captured by the surveillance variables country of birth and citizenship. Surveillance systems in Western Europe should allow for quantifying the tuberculosis burden in this important risk group. PMID:26061733

  20. Comparing variation in hospital rates of cesarean delivery among low-risk women using 3 different measures.

    PubMed

    Armstrong, Joanne C; Kozhimannil, Katy B; McDermott, Patricia; Saade, George R; Srinivas, Sindhu K

    2016-02-01

    This report describes the development of a measure of low-risk cesarean delivery by the Society for Maternal-Fetal Medicine (SMFM). Safely lowering the cesarean delivery rate is a priority for maternity care clinicians and health care delivery systems. Therefore, hospital quality assurance programs are increasingly tracking cesarean delivery rates among low-risk pregnancies. Two commonly used definitions of "low risk" are available, the Joint Commission (JC) and the Agency for Healthcare Research and Quality (AHRQ) measures, but these measures are not clinically comprehensive. We sought to refine the definition of the low-risk cesarean delivery rate to enhance the validity of the metric for quality measurement. We created this refined definition-called the SMFM definition-and compared it to the JC and AHRQ measures using claims-based data from the 2011 Nationwide Inpatient Sample of >863,000 births in 612 hospitals. Using these definitions, we calculated means and interquartile ranges (25th-75th percentile range) for hospital low-risk cesarean delivery rates, stratified by hospital size, teaching status, urban/rural location, and payer mix. Across all hospitals, the mean low-risk cesarean delivery rate was lowest for the SMFM definition (12.65%), but not substantially different from the JC and AHRQ measures (13.12% and 13.29%, respectively). We empirically examined the SMFM definition to ensure its validity and utility. This refined definition performs similarly to existing measures and has the added advantage of clinical perspective, enhanced face validity, and ease of use. PMID:26593970

  1. The dark energy survey Y1 supernova search: Survey strategy compared to forecasts and the photometric type Is SN volumetric rate

    NASA Astrophysics Data System (ADS)

    Fischer, John Arthur

    For 70 years, the physics community operated under the assumption that the expansion of the Universe must be slowing due to gravitational attraction. Then, in 1998, two teams of scientists used Type Ia supernovae to discover that cosmic expansion was actually acceler- ating due to a mysterious "dark energy." As a result, Type Ia supernovae have become the most cosmologically important transient events in the last 20 years, with a large amount of effort going into their discovery as well as understanding their progenitor systems. One such probe for understanding Type Ia supernovae is to use rate measurements to de- termine the time delay between star formation and supernova explosion. For the last 30 years, the discovery of individual Type Ia supernova events has been accelerating. How- ever, those discoveries were happening in time-domain surveys that probed only a portion of the redshift range where expansion was impacted by dark energy. The Dark Energy Survey (DES) is the first project in the "next generation" of time-domain surveys that will discovery thousands of Type Ia supernovae out to a redshift of 1.2 (where dark energy be- comes subdominant) and DES will have better systematic uncertainties over that redshift range than any survey to date. In order to gauge the discovery effectiveness of this survey, we will use the first season's 469 photometrically typed supernovee and compare it with simulations in order to update the full survey Type Ia projections from 3500 to 2250. We will then use 165 of the 469 supernovae out to a redshift of 0.6 to measure the supernovae rate both as a function of comoving volume and of the star formation rate as it evolves with redshift. We find the most statistically significant prompt fraction of any survey to date (with a 3.9? prompt fraction detection). We will also reinforce the already existing tension in the measurement of the delayed fraction between high (z > 1.2) and low red- shift rate measurements, where we find no

  2. Nile Delta exhibited a spatial reversal in the rates of shoreline retreat on the Rosetta promontory comparing pre- and post-beach protection

    NASA Astrophysics Data System (ADS)

    Ghoneim, Eman; Mashaly, Jehan; Gamble, Douglas; Halls, Joanne; AbuBakr, Mostafa

    2015-01-01

    The coastline of the Nile Delta experienced accelerated erosion since the construction of the Aswan High Dam in 1964 and, consequently, the entrapment of a large amount of river sediments behind it. The coastline of the Rosetta promontory showed the highest erosion in the Delta with an average retreat rate of 137.4 m year- 1. In 1991, in an effort to mitigate sediment loss, a 4.85 km long seawall was built on the outer margin of the promontory. For additional beach protection, 15 groins were constructed along the eastern and western sides of the seawall in 2003 and 2005. To quantify erosion and accretion patterns along the Rosetta promontory, 11 Landsat images acquired at unequal intervals during a 40 year time span (1972 and 2012) were analyzed. The positions of shorelines were automatically extracted from satellite imagery and compared with three very high resolution QuickBird and WorldView2 images for data validation. Analysis of the rates of shoreline change revealed that the construction of the seawall was largely successful in halting the recession along the tip of the promontory, which lost 10.8 km2 prior to coastal protection. Conversely, the construction of the 15 groins has negatively affected the coastal morphology of the promontory and caused a reversal from accretion to fast erosion along the promontory leeside, where some segments of the shoreline have undergone as much as 30.8 m year- 1 of erosion. Without hard structures, the tip of the Rosetta promontory would have retreated 2.3 km by 2013 and lost 7.2 km2 of land. About 10% of this land is deltaic fertile cultivated farms. Moreover, without additional protection the sides of the promontory will lose about 1.3 km2 of land and the coastline would recede at an average rate of 200 m by 2020. Unless action is taken, coastal erosion, enhanced by rising sea level, will steadily eat away the Nile Delta at an alarming rate. The successful demonstration of the advocated procedures in this study could be

  3. Ablation of atheroma by laser energy: a comparative study of the efficacy of different temporal rates of energy deposition

    NASA Astrophysics Data System (ADS)

    Ramsay, Donald J.; Walker, Philip J.; Dadswell, Nicola G.; May, James; Piper, James A.; Wacher, Christine

    1990-06-01

    Laser angioplasty continues to attract interest as a potential method for treating atherosclerotic arterial disease. Current efforts are aimed at finding the most effective combination of laser and delivery system. High energy pulsed ultraviolet or infrared lasers demonstrate good photoablative properties but there remain practical difficulties with the optical fibre delivery. Continuous wave lasers are widely used in conjunction with "hot-tip" fibres for thermal ablation but their direct (optical) ablation efficiency is low, causing significant surrounding thermal damage in soft tissue. While considerable attention has been directed previously at the ablative effects for different laser wavelengths, little systematic study has been made of the efficacy for different temporal rates of energy deposition. We have compared the efficacy for tissue ablation in cadaveric human aorta of three different laser systems with similar wavelengths in the visible (green) but different temporal rates of energy deposition. The laser sources were the continuous wave argon ion laser (514.5 nm), the high pulse energy, frequency doubled Nd:YAG laser (532 nm) and the copper vapour laser. The copper vapour laser is a high repetition rate, high average power, pulsed laser emitting in the green (511 nm) and yellow (578 nm) which has temporal characteristics intermediate between those of the Nd:YAG laser and the argon ion laser, and has the potential to be effective both for direct optical ablation and hot-tip thermal ablation.

  4. Exact solution of the one- and three-dimensional quantum kinetic equations with velocity-dependent collision rates: Comparative analysis

    NASA Astrophysics Data System (ADS)

    Privalov, T.; Shalagin, A.

    1999-06-01

    The interaction of a plane monochromatic traveling wave with two-level particles suffering collisions with buffer-gas particles is considered. Collision rates are assumed to be velocity dependent. The collision integral is obtained on the basis of the strong-collision model, generalized to the case of velocity-dependent collision rates (the so-called ``kangaroo'' model). We obtained the exact analytical solution of the problem for arbitrary intensity of radiation, arbitrary ratio of homogeneous and Doppler widths of the absorption line, and arbitrary mass ratio between absorbing- and buffer-gas particles. The obtained analytical solutions of the quantum kinetic equations allowed us to analyze the spectral shape of the strong-field absorption line as well as the probe-field absorption line (the nonlinear part of the work done by the probe field) and the frequency dependence of the light-induced drift (LID) velocity. A comprehensive comparative analysis for the three- and one-dimensional versions of the model is given. On the basis of this analysis, we reach the conclusion that the one-dimensional quantum kinetic equation has quite a wide range of application. We also reveal the conditions for the strongest manifestation of the velocity dependence of the collision rates, which affects most strongly the anomalous LID.

  5. A systematic study on the reactivity of different grades of charged Li[NixMnyCoz]O2 with electrolyte at elevated temperatures using accelerating rate calorimetry

    NASA Astrophysics Data System (ADS)

    Ma, Lin; Nie, Mengyun; Xia, Jian; Dahn, J. R.

    2016-09-01

    The reactivity between charged Li[NixMnyCoz]O2 (NMC, with x + y + z = 1, x:y:z = 1:1:1 (NMC111), 4:4:2 (NMC442), 5:3:2 (NMC532), 6:2:2 (NMC622) and 8:1:1 (NMC811)) and traditional carbonate-based electrolytes at elevated temperatures was systematically studied using accelerating rate calorimetry (ARC). The ARC results showed that the upper cut-off potential and NMC composition strongly affect the thermal stability of the various NMC grades when traditional carbonate-based electrolyte was used. Although higher cut-off potential and higher Ni content can help increase the energy density of lithium ion cells, these factors generally increase the reactivity between charged NMC and electrolyte at elevated temperatures. It is hoped that this report can be used to help guide the wise selection of NMC grade and upper cut-off potential to achieve high energy density Li-ion cells without seriously compromising cell safety.

  6. Predicting electrical and thermal abuse behaviours of practical lithium-ion cells from accelerating rate calorimeter studies on small samples in electrolyte

    NASA Astrophysics Data System (ADS)

    Richard, M. N.; Dahn, J. R.

    An accelerating rate calorimeter (ARC) is used to measure the thermal stability of de-intercalated Li 1+ xMn 2- xO 4 in LiPF 6 EC:DEC (33:67) electrolyte. Self-heating is detected well after the 80°C onset of self-heating measured for lithium intercalated mesocarbon microbead (MCMB) electrodes in LiPF 6 EC:DEC (33:67) electrolyte. As a result, the initial self-heating measured in a practical carbon/Li 1+ xMn 2- xO 4 lithium-ion cell is caused by reactions at the anode. In previous work, we have proposed a model for the reactions that cause self-heating in MCMB electrodes in electrolyte. By assuming that a cell self-heats only because reactions occur at the anode, the model can be used to predict the power generated by the amount of MCMB in practical cells with an inert cathode. The calculated chemically generated power can be combined with power loss measurements, due to the transfer of heat to the environment, to predict the short-circuit behaviour and the oven exposure behaviour for a cell containing an MCMB anode and an inert cathode. The results agree qualitatively with short-circuit and oven exposure results measured on NEC Moli energy 18650 cells containing an Li 1+ xMn 2- xO 4 cathode.

  7. A comparative study of the indoor radon level with the radon exhalation rate from soil in Alexandria city.

    PubMed

    Abd El-Zaher, Mohamed

    2013-05-01

    The assessment of the radiological risk related to the inhalation of radon and radon its progeny is based mainly on the integrated measurement of radon in both indoor and outdoor environments. The exhalation of radon from the earth's crust and building materials forms the main source of radon in the indoor environment. This study has been undertaken for the purpose of health risk assessment. In this comparative study, the indoor radon level, radium content, radon exhalation rate and concentration of soil radon are measured using the Can Technique. Soil samples were collected simultaneously from different geological formations of the same area for laboratory measurement of the radon exhalation rate. The radon exhalation rate was measured in the laboratory using LR-115 type II plastic track detectors. The indoor radon concentrations in this study area were found to vary from 44±9 to 132±31 Bq m(-3) with an average of 72±29 Bq m(-3). The seasonal variations of the indoor radon reveal the maximum values in the winter and in summer in different dwellings of Alexandria city. The annual effective dose varies from 0.75 to 2.2 mSv with an average value of 1.34 mSv. The radon exhalation rate was found to vary in the ranges 8.31-233.70×10(-3) Bq kg(-1) h(-1), 0.48-15.37 Bq m(-2) h(-1) with an average 47.97×10(-3) Bq kg(-1) h(-1), (3.14 Bq m(-2) h(-1)). The radium content in soil varies from 3.14 to 39.60 Bq kg(-1) with an average of 11.55 Bq kg(-1). The significance of this study is discussed in details from the point of view of radiation protection. PMID:23070484

  8. Individualized Positron Emission Tomography–Based Isotoxic Accelerated Radiation Therapy Is Cost-Effective Compared With Conventional Radiation Therapy: A Model-Based Evaluation

    SciTech Connect

    Bongers, Mathilda L.; Coupé, Veerle M.H.; De Ruysscher, Dirk; Oberije, Cary; Lambin, Philippe; Uyl-de Groot, Cornelia A.

    2015-03-15

    Purpose: To evaluate long-term health effects, costs, and cost-effectiveness of positron emission tomography (PET)-based isotoxic accelerated radiation therapy treatment (PET-ART) compared with conventional fixed-dose CT-based radiation therapy treatment (CRT) in non-small cell lung cancer (NSCLC). Methods and Materials: Our analysis uses a validated decision model, based on data of 200 NSCLC patients with inoperable stage I-IIIB. Clinical outcomes, resource use, costs, and utilities were obtained from the Maastro Clinic and the literature. Primary model outcomes were the difference in life-years (LYs), quality-adjusted life-years (QALYs), costs, and the incremental cost-effectiveness and cost/utility ratio (ICER and ICUR) of PET-ART versus CRT. Model outcomes were obtained from averaging the predictions for 50,000 simulated patients. A probabilistic sensitivity analysis and scenario analyses were carried out. Results: The average incremental costs per patient of PET-ART were €569 (95% confidence interval [CI] €−5327-€6936) for 0.42 incremental LYs (95% CI 0.19-0.61) and 0.33 QALYs gained (95% CI 0.13-0.49). The base-case scenario resulted in an ICER of €1360 per LY gained and an ICUR of €1744 per QALY gained. The probabilistic analysis gave a 36% probability that PET-ART improves health outcomes at reduced costs and a 64% probability that PET-ART is more effective at slightly higher costs. Conclusion: On the basis of the available data, individualized PET-ART for NSCLC seems to be cost-effective compared with CRT.

  9. Higher rate of fat oxidation during rowing compared with cycling ergometer exercise across a range of exercise intensities.

    PubMed

    Egan, B; Ashley, D T; Kennedy, E; O'Connor, P L; O'Gorman, D J

    2016-06-01

    The relative contribution of carbohydrate and fat oxidation to energy expenditure during exercise is dependent on variables including exercise intensity, mode, and recruited muscle mass. This study investigated patterns of substrate utilization during two non-weightbearing exercise modalities, namely cycling and rowing. Thirteen young, moderately trained males performed a continuous incremental (3-min stages) exercise test to exhaustion on separate occasions on an electronically braked cycle (CYC) ergometer and an air-braked rowing (ROW) ergometer, respectively. On two further occasions, participants performed a 20-min steady-state exercise bout at ∼50%VO2peak on the respective modalities. Despite similar oxygen consumption, rates of fat oxidation (FATox ) were ∼45% higher during ROW compared with CYC (P < 0.05) across a range of power output increments. The crossover point for substrate utilization occurred at a higher relative exercise intensity for ROW than CYC (57.8 ± 2.1 vs 42.1 ± 3.6%VO2peak , P < 0.05). During steady-state submaximal exercise, the higher FATox during ROW compared with CYC was maintained (P < 0.05), but absolute FATox were 42% (CYC) and 28% (ROW) lower than during incremental exercise. FATox is higher during ROW compared with CYC exercise across a range of exercise intensities matched for energy expenditure, and is likely as a consequence of larger muscle mass recruited during ROW. PMID:26060092

  10. Plasma production for electron acceleration by resonant plasma wave

    NASA Astrophysics Data System (ADS)

    Anania, M. P.; Biagioni, A.; Chiadroni, E.; Cianchi, A.; Croia, M.; Curcio, A.; Di Giovenale, D.; Di Pirro, G. P.; Filippi, F.; Ghigo, A.; Lollo, V.; Pella, S.; Pompili, R.; Romeo, S.; Ferrario, M.

    2016-09-01

    Plasma wakefield acceleration is the most promising acceleration technique known nowadays, able to provide very high accelerating fields (10-100 GV/m), enabling acceleration of electrons to GeV energy in few centimeter. However, the quality of the electron bunches accelerated with this technique is still not comparable with that of conventional accelerators (large energy spread, low repetition rate, and large emittance); radiofrequency-based accelerators, in fact, are limited in accelerating field (10-100 MV/m) requiring therefore hundred of meters of distances to reach the GeV energies, but can provide very bright electron bunches. To combine high brightness electron bunches from conventional accelerators and high accelerating fields reachable with plasmas could be a good compromise allowing to further accelerate high brightness electron bunches coming from LINAC while preserving electron beam quality. Following the idea of plasma wave resonant excitation driven by a train of short bunches, we have started to study the requirements in terms of plasma for SPARC_LAB (Ferrario et al., 2013 [1]). In particular here we focus on hydrogen plasma discharge, and in particular on the theoretical and numerical estimates of the ionization process which are very useful to design the discharge circuit and to evaluate the current needed to be supplied to the gas in order to have full ionization. Eventually, the current supplied to the gas simulated will be compared to that measured experimentally.

  11. The logic of comparative life history studies for estimating key parameters, with a focus on natural mortality rate

    USGS Publications Warehouse

    Hoenig, John M; Then, Amy Y.-H.; Babcock, Elizabeth A.; Hall, Norman G.; Hewitt, David A.; Hesp, Sybrand A.

    2016-01-01

    There are a number of key parameters in population dynamics that are difficult to estimate, such as natural mortality rate, intrinsic rate of population growth, and stock-recruitment relationships. Often, these parameters of a stock are, or can be, estimated indirectly on the basis of comparative life history studies. That is, the relationship between a difficult to estimate parameter and life history correlates is examined over a wide variety of species in order to develop predictive equations. The form of these equations may be derived from life history theory or simply be suggested by exploratory data analysis. Similarly, population characteristics such as potential yield can be estimated by making use of a relationship between the population parameter and bio-chemico–physical characteristics of the ecosystem. Surprisingly, little work has been done to evaluate how well these indirect estimators work and, in fact, there is little guidance on how to conduct comparative life history studies and how to evaluate them. We consider five issues arising in such studies: (i) the parameters of interest may be ill-defined idealizations of the real world, (ii) true values of the parameters are not known for any species, (iii) selecting data based on the quality of the estimates can introduce a host of problems, (iv) the estimates that are available for comparison constitute a non-random sample of species from an ill-defined population of species of interest, and (v) the hierarchical nature of the data (e.g. stocks within species within genera within families, etc., with multiple observations at each level) warrants consideration. We discuss how these issues can be handled and how they shape the kinds of questions that can be asked of a database of life history studies.

  12. A study in normal human volunteers to compare the rate and extent of levothyroxine absorption from Synthroid and Levoxine.

    PubMed

    Berg, J A; Mayor, G H

    1992-12-01

    Numerous branded and generic formulations of levothyroxine (LT4) sodium tablets are currently available. Results from previous studies attempting to examine the comparative bioavailability of these formulations are difficult to interpret because of subject heterogeneity, single time-point blood sampling, varying degrees of hypothyroidism, and other factors. This study was devised to compare the rate and extent of absorption of LT4 from different LT4 sodium tablet formulations, in a simple model using a single-dose two-way single-blind, randomized cross-over design in 30 normal, healthy, nonpregnant, female subjects. This design controlled for many factors that limited previous LT4 bioavailability studies. Subjects were given a single 600 micrograms dose of LT4 as either Synthroid (Boots Pharmaceuticals, Inc., Lincolnshire, IL) tablets (formulation A) or Levoxine tablets (Daniels Pharmaceuticals, St. Petersburg, FL; formulation B). Measurements of baseline-corrected total T4 serum concentrations determined at multiple time points demonstrated statistically significant differences between the two formulations at the 1.00, 3.00, 5.00, and 18.00 hour sampling times. Statistically significant differences for area under the curve (AUC) (0 to 48 hours) (formulation A, 159.9 +/- 9.4 micrograms-hour/dL; formulation B, 193.4 +/- 10.1 micrograms-hour/dL) and maximum peak plasma concentration (Cmax) (formulation A, 5.91 +/- .34; formulation B, 7.12 +/- .32) also were demonstrated. Furthermore, the ratio of the baseline-corrected total T4 concentrations (B/A x 100) were 120.9% for AUC and 120.5% for Cmax. These data demonstrate that the administration of Synthroid and Levoxine result in a significantly different rate and extent of absorption of LT4, and therefore these two formulations cannot be considered bioequivalent.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1487553

  13. A Retrospective Cohort Study Comparing Stroke Recurrence Rate in Ischemic Stroke Patients With and Without Acupuncture Treatment.

    PubMed

    Shih, Chun-Chuan; Liao, Chien-Chang; Sun, Mao-Feng; Su, Yi-Chang; Wen, Chi-Pang; Morisky, Donald E; Sung, Fung-Chang; Hsu, Chung Y; Lin, Jaung-Geng

    2015-09-01

    Little was known about the effects of acupuncture on stroke recurrence. The aim of this study is to investigate whether ischemic stroke patients receiving acupuncture treatment have a decreased risk of stroke recurrence. A retrospective cohort study of 30,058 newly diagnosed cases of ischemic stroke in 2000 to 2004 was conducted based on the claims of Taiwan National Health Insurance Research Database. The use of acupuncture treatment and stroke recurrence were identified during the follow-up period from 2000 to 2009. This study compared the risk of stroke recurrence between ischemic stroke cohorts with and without acupuncture treatment by calculating adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of acupuncture associated with stroke recurrence in the Cox proportional hazard model. The stroke recurrence rate per 1000 person-years decreased from 71.4 without to 69.9 with acupuncture treatment (P < 0.001). Acupuncture treatment was associated with reduced risk of stroke recurrence (HR 0.88; 95% CI 0.84-0.91). The acupuncture effect was noted in patients with or without medical treatment for stroke prevention but its impact decreased with aging of stroke patients. Compared with stroke patients without acupuncture treatment and medication therapy, the hazard ratios of stroke recurrence for those had medication therapy only, acupuncture only, and both were 0.42 (95% CI 0.38-0.46), 0.50 (95% CI 0.43-0.57), and 0.39 (95% CI 0.35-0.43), respectively. This study raises the possibility that acupuncture might be effective in lowering stroke recurrence rate even in those on medications for stroke prevention. Results suggest the need of prospective sham-controlled and randomized trials to establish the efficacy of acupuncture in preventing stroke. PMID:26426630

  14. A Retrospective Cohort Study Comparing Stroke Recurrence Rate in Ischemic Stroke Patients With and Without Acupuncture Treatment

    PubMed Central

    Shih, Chun-Chuan; Liao, Chien-Chang; Sun, Mao-Feng; Su, Yi-Chang; Wen, Chi-Pang; Morisky, Donald E.; Sung, Fung-Chang; Hsu, Chung Y.; Lin, Jaung-Geng

    2015-01-01

    Abstract Little was known about the effects of acupuncture on stroke recurrence. The aim of this study is to investigate whether ischemic stroke patients receiving acupuncture treatment have a decreased risk of stroke recurrence. A retrospective cohort study of 30,058 newly diagnosed cases of ischemic stroke in 2000 to 2004 was conducted based on the claims of Taiwan National Health Insurance Research Database. The use of acupuncture treatment and stroke recurrence were identified during the follow-up period from 2000 to 2009. This study compared the risk of stroke recurrence between ischemic stroke cohorts with and without acupuncture treatment by calculating adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of acupuncture associated with stroke recurrence in the Cox proportional hazard model. The stroke recurrence rate per 1000 person-years decreased from 71.4 without to 69.9 with acupuncture treatment (P < 0.001). Acupuncture treatment was associated with reduced risk of stroke recurrence (HR 0.88; 95% CI 0.84–0.91). The acupuncture effect was noted in patients with or without medical treatment for stroke prevention but its impact decreased with aging of stroke patients. Compared with stroke patients without acupuncture treatment and medication therapy, the hazard ratios of stroke recurrence for those had medication therapy only, acupuncture only, and both were 0.42 (95% CI 0.38–0.46), 0.50 (95% CI 0.43–0.57), and 0.39 (95% CI 0.35–0.43), respectively. This study raises the possibility that acupuncture might be effective in lowering stroke recurrence rate even in those on medications for stroke prevention. Results suggest the need of prospective sham-controlled and randomized trials to establish the efficacy of acupuncture in preventing stroke. PMID:26426630

  15. Accelerated partial breast irradiation: An analysis of variables associated with late toxicity and long-term cosmetic outcome after high-dose-rate interstitial brachytherapy

    SciTech Connect

    Wazer, David E. . E-mail: dwazer@tufts-nemc.org; Kaufman, Seth; Cuttino, Laurie; Di Petrillo, Thomas; Arthur, Douglas W.

    2006-02-01

    Purpose: To perform a detailed analysis of variables associated with late tissue effects of high-dose-rate (HDR) interstitial brachytherapy accelerated partial breast irradiation (APBI) in a large cohort of patients with prolonged follow-up. Methods and Materials: Beginning in 1995, 75 women with Stage I/II breast cancer were enrolled in identical institutional trials evaluating APBI as monotherapy after lumpectomy. Patients eligible included those with T1-2, N0-1 ({<=}3 nodes positive), M0 tumors of nonlobular histology with negative surgical margins, no extracapsular nodal extension, and negative results on postexcision mammogram. All patients underwent surgical excision and postoperative irradiation with HDR interstitial brachytherapy. The planning target volume was defined as the excision cavity plus a 2-cm margin. Treatment was delivered with a high-activity Ir-192 source at 3.4 Gy per fraction twice daily for 5 days to a total dose of 34 Gy. Dosimetric analyses were performed with three-dimensional postimplant dose and volume reconstructions. All patients were evaluated at 3-6-month intervals and assessed with a standardized cosmetic rating scale and according to Radiation Therapy Oncology Group late normal tissue toxicity scoring criteria. Clinical and therapy-related features were analyzed for their relationship to cosmetic outcome and toxicity rating. Clinical features analyzed included age, volume of resection, history of diabetes or hypertension, extent of axillary surgery, and systemic therapies. Therapy-related features analyzed included volume of tissue encompassed by the 100%, 150%, and 200% isodose lines (V100, V150, and V200, respectively), the dose homogeneity index (DHI), number of source dwell positions, and planar separation. Results: The median follow-up of all patients was 73 months (range, 43-118 months). The cosmetic outcome at last follow-up was rated as excellent, good, and fair/poor in 67%, 24%, and 9% of patients, respectively

  16. A Comparative Analysis of Dietary Habits on Sensory Motor Association and Heart Rate Variability during Menstrual Cycle

    PubMed Central

    Alam, Tanwir; Jiwane, Rekha; Kishanrao, Sadawarte Sahebrao

    2016-01-01

    Introduction Dietary habits can make a big difference on both physical and mental aspects of the body. Menstrual disorder frequently affects the quality of life of adolescent and young adult women. Menstrual cycle irregularities may be associated with psychological stress, and endocrine disturbances. Monitoring of sensory-motor association and cardiovascular activity across the menstrual cycle has not been evaluated with dietary habits. Aim The present study was carried out to bridge the relationship between dietary habits and endogenous sex hormone mediated sensory motor association and heart rate variability (HRV) among young females during different phases of menstrual cycle. Materials and Methods The present study was carried out on healthy volunteered 100 female medical students in the age group of 19-25 years with regular menstrual cycle. Group I (n=45) vegetarians, Group II (n=25) eggetarians and Group III (n= 30) non-vegetarians, where n denotes the number of individuals in each group. Sensory-motor association (reaction time) and cardiovascular activity (HRV) was evaluated. Results We observed among all the dietary habits (vegetarians, eggetarians and non-vegetarians) the reaction time and HRV was comparable in follicular and menstrual phase, however it was significantly altered in luteal phase when compared to follicular and menstrual phase. Moreover, among all the dietary habits, non-vegetarians showed more significant alteration of reaction time and HRV in luteal phase when compared to vegetarians and eggetarians, as well as there was positive correlation between visual and auditory reaction time and negative correlation between LF and HF in luteal phase, among all the dietary habits. Conclusion We concluded sensorimotor association and regulation of autonomic tone is modified in luteal phase comparable to follicular phase and menstrual phase; however non-vegetarian had showed more significant alterations as compared to eggetarians and vegetarians

  17. Work Hours and Self rated Health of Hospital Doctors in Norway and Germany. A comparative study on national samples

    PubMed Central

    2011-01-01

    Background The relationship between extended work hours and health is well documented among hospital doctors, but the effect of national differences in work hours on health is unexplored. The study examines the relationship between work hours and self rated health in two national samples of hospital doctors. Methods The study population consisted of representative samples of 1,260 German and 562 Norwegian hospital doctors aged 25-65 years (N = 1,822) who received postal questionnaires in 2006 (Germany) and 2008 (Norway). The questionnaires contained items on demography, work hours (number of hours per workday and on-call per month) and self rated subjective health on a five point scale - dichotomized into "good" (above average) and "average or below". Results Compared to Norway, a significantly higher proportion of German doctors exceeded a 9 hour work day (58.8% vs. 26.7%) and 60 hours on-call per month (63.4% vs. 18.3%). Every third (32.2%) hospital doctor in Germany worked more than this, while this pattern was rare in Norway (2.9%). In a logistic regression model, working in Norway (OR 4.17; 95% CI 3.02-5.73), age 25-44 years (OR 1.66; 95% CI 1.29-2.14) and not exceeding 9 hour work day and 60 hours on-call per month (OR 1.35; 95% CI 1.03-1.77) were all independent significant predictors of good self reported health. Conclusion A lower percentage of German hospital doctors reported self rated health as "good", which is partly explained by the differences in work time pattern. Initiatives to increase doctors' control over their work time are recommended. PMID:21338494

  18. Comparable High Rates of Extended-Spectrum-Beta-Lactamase-Producing Escherichia coli in Birds of Prey from Germany and Mongolia

    PubMed Central

    Guenther, Sebastian; Aschenbrenner, Katja; Stamm, Ivonne; Bethe, Astrid; Semmler, Torsten; Stubbe, Annegret; Stubbe, Michael; Batsajkhan, Nyamsuren; Glupczynski, Youri; Wieler, Lothar H.; Ewers, Christa

    2012-01-01

    Frequent contact with human waste and liquid manure from intensive livestock breeding, and the increased loads of antibiotic-resistant bacteria that result, are believed to be responsible for the high carriage rates of ESBL-producing E. coli found in birds of prey (raptors) in Central Europe. To test this hypothesis against the influence of avian migration, we initiated a comparative analysis of faecal samples from wild birds found in Saxony-Anhalt in Germany and the Gobi-Desert in Mongolia, regions of dissimilar human and livestock population characteristics and agricultural practices. We sampled a total of 281 wild birds, mostly raptors with primarily north-to-south migration routes. We determined antimicrobial resistance, focusing on ESBL production, and unravelled the phylogenetic and clonal relatedness of identified ESBL-producing E. coli isolates using multi-locus sequence typing (MLST) and macrorestriction analyses. Surprisingly, the overall carriage rates (approximately 5%) and the proportion of ESBL-producers among E. coli (Germany: 13.8%, Mongolia: 10.8%) were similar in both regions. Whereas blaCTX-M-1 predominated among German isolates (100%), blaCTX-M-9 was the most prevalent in Mongolian isolates (75%). We identified sequence types (STs) that are well known in human and veterinary clinical ESBL-producing E. coli (ST12, ST117, ST167, ST648) and observed clonal relatedness between a Mongolian avian ESBL-E. coli (ST167) and a clinical isolate of the same ST that originated in a hospitalised patient in Europe. Our data suggest the influence of avian migratory species in the transmission of ESBL-producing E. coli and challenge the prevailing assumption that reducing human influence alone invariably leads to lower rates of antimicrobial resistance. PMID:23300857

  19. A comparative analysis of infiltration rates below a pasture and a secondary forest on Santa Cruz Island, Galapagos

    NASA Astrophysics Data System (ADS)

    d'Ozouville, N.; Pryet, A.; Tournebize, J.; Chaumont, C.; Gonzáles, A.; Dominguez, C.; Fuente-Tomai, P.; Fernandez, J.; Violette, S.

    2011-12-01

    The potential effects of land use changes on groundwater recharge are being investigated on the windward side of Santa Cruz Island, Galapagos. Comparative studies allow the identification of the processes (evaporation, transpiration, soil water storage) at the vegetation/soil interface leading to contrasting recharge rates under different land covers. During one year, we monitored soil water dynamics under two adjacent study plots differing only by their vegetation cover: a pasture and a secondary forest. Climatic variables were monitored above the pasture and completed by throughfall monitoring under the forest. Tensiometers provide a direct measurement of the driving force of water dynamics in the soil: the hydraulic head gradient. In the two plots, tensiometers were set up in vertical profiles together with soil water content probes and connected to an automatic acquisition device. The forest stand has a higher canopy storage capacity and aerodynamic resistance, which causes evaporation losses to be higher. This is confirmed by throughfall measurements: only ca. 80% of gross precipitation reaches the ground. Expectedly, soil water tension profiles present clearly different behaviors in the pasture and in the forest. Despite high uncertainties on estimated recharge rates, we show that parallel monitoring of soil hydrodynamics in these two study plots provides valuable insights and may help to manage or anticipate the potential effect of deforestation or invasion by introduced plants on the hydrology of Santa Cruz Island, Galapagos.

  20. Accelerated partial breast irradiation using intensity-modulated radiotherapy technique compared to whole breast irradiation for patients aged 70 years or older: subgroup analysis from a randomized phase 3 trial.

    PubMed

    Meattini, Icro; Saieva, Calogero; Marrazzo, Livia; Di Brina, Lucia; Pallotta, Stefania; Mangoni, Monica; Meacci, Fiammetta; Bendinelli, Benedetta; Francolini, Giulio; Desideri, Isacco; De Luca Cardillo, Carla; Scotti, Vieri; Furfaro, Ilaria Francesca; Rossi, Francesca; Greto, Daniela; Bonomo, Pierluigi; Casella, Donato; Bernini, Marco; Sanchez, Luis; Orzalesi, Lorenzo; Simoncini, Roberta; Nori, Jacopo; Bianchi, Simonetta; Livi, Lorenzo

    2015-10-01

    The purpose of this study was to report the efficacy and the safety profile on the subset of selected early breast cancer (BC) patients aged 70 years or older from a single-center phase 3 trial comparing whole breast irradiation (WBI) to accelerated partial breast irradiation (APBI) using intensity-modulated radiation therapy technique. Between 2005 and 2013, 520 patients aged more than 40 years old were enrolled and randomly assigned to receive either WBI or APBI in a 1:1 ratio. Eligible patients were women with early BC (maximum diameter 2.5 cm) suitable for breast conserving surgery. This study is registered with ClinicalTrials.gov, NCT02104895. A total of 117 patients aged 70 years or more were analyzed (58 in the WBI arm, 59 in the APBI arm). At a median follow-up of 5-years (range 3.4-7.0), the ipsilateral breast tumor recurrence (IBTR) rate was 1.9 % in both groups. No significant difference between the two groups was identified (log-rank test p = 0.96). The 5-year disease-free survival (DFS) rates in the WBI group and APBI group were 6.1 and 1.9 %, respectively (p = 0.33). The APBI group presented significantly better results in terms of acute skin toxicity, considering both any grade (p = 0.0001) and grade 2 or higher (p = 0.0001). Our subgroup analyses showed a very low rate and no significant difference in terms of IBTR, using both WBI and APBI. A significant impact on patients compliance in terms of acute and early late toxicity was shown, which could translate in a consistent improvement of overall quality of life. PMID:26350524

  1. Metabolic acceleration in Mediterranean Perciformes

    NASA Astrophysics Data System (ADS)

    Lika, Konstadia; Kooijman, Sebastiaan A. L. M.; Papandroulakis, Nikos

    2014-11-01

    Larval stages are considered the most critical of fish development. During a very short period of time (2 to 3 months), larvae undergo major morphoanatomical and functional changes in order to transform into juveniles while remaining functioning (developing, eating, surviving). Depending on species and environmental conditions, patterns in larval development may vary. We study the patterns of larval development for nine fish species of Perciformes reared under aquaculture conditions and compare them in terms of species-specific parameters derived from DEB theory. We extended the standard DEB model to include metabolic acceleration during the larval period, where maximum specific assimilation and energy conductance increase with length between birth and metabolic metamorphosis. Metabolic acceleration has as a consequence that larvae initially grow slower than juveniles and adults. Our results indicate that the species with higher acceleration have lower growth rates at birth and they also suggest that metabolic acceleration is related to spawning season. High metabolic acceleration of demersal species is associated with summer-autumn spawning in the Mediterranean, where temperature is high and food availability is low.

  2. A 6-year comparative economic evaluation of healthcare costs and mortality rates of Dutch patients from conventional and CAM GPs

    PubMed Central

    Baars, Erik W; Kooreman, Peter

    2014-01-01

    Objectives To compare healthcare costs and mortality rates of Dutch patients with a conventional (CON) general practitioner (GP) and patients with a GP who has additionally completed training in complementary and alternative medicine (CAM). Design Comparative economic evaluation. Setting Database from the Dutch insurance company Agis. Participants 1 521 773 patients (98.8%) from a CON practice and 18 862 patients (1.2%) from a CAM practice. Main outcome measures Annual information on five types of healthcare costs for the years 2006–2011: care by GP, hospital care, pharmaceutical care, paramedic care and care covered by supplementary insurance. Healthcare costs in the last year of life. Mortality rates. Results The mean annual compulsory and supplementary healthcare costs of CON patients are respectively €1821 (95% CI 1813 to 1828) and €75.3 (95% CI 75.1 to 75.5). Compulsory healthcare costs of CAM patients are €225 (95% CI 169 to 281; p<0.001; 12.4%) lower and result mainly from lower hospital care costs (€165; 95% CI 118 to 212; p<0.001) and lower pharmaceutical care costs (€58; 95% CI 41 to 75; p<0.001), especially in the age categories 25–49 and 50–74 years. The costs in the last year of life of patients with CAM, GPs are €1161 (95% CI −138 to 2461; p<0.1) lower. This difference is entirely due to lower hospital costs (€1250; 95% CI 19 to 2481; p<0.05). The mean annual supplementary costs of CAM patients are €33 (95% CI 30 to 37; p<0.001; 44%) higher. CAM patients do not have lower or higher mortality rates than CON patients. Conclusions Dutch patients whose GP additionally completed training in CAM on average have €192 (10.1%) lower annual total compulsory and supplementary healthcare costs and do not live longer or shorter than CON patients. PMID:25164536

  3. Comparing Cultural Differences in Two Quality Measures in Chinese Kindergartens: The Early Childhood Environment Rating Scale-Revised and the Kindergarten Quality Rating System

    ERIC Educational Resources Information Center

    Hu, Bi Ying

    2015-01-01

    This study examined the degrees of congruence between two early childhood evaluation systems on various quality concepts: the Early Childhood Environment Rating Scale-Revised (ECERS-R) and Zhejiang's Kindergarten Quality Rating System (KQRS). Analysis of variance and post hoc least significant difference tests were employed to show the extent…

  4. Comparative study of the corrosion behavior of peripheral stents in an accelerated corrosion model: experimental in vitro study of 28 metallic vascular endoprostheses

    PubMed Central

    Paprottka, Karolin J.; Paprottka, Philipp M.; Reiser, Maximilian F.; Waggershauser, Tobias

    2015-01-01

    PURPOSE Clinical cases of stent-fractures show that corrosion behavior might play a role in these fractures. Implanted in vivo, especially in combination with other implanted foreign materials, these metallic products are exposed to special conditions, which can cause a process of corrosion. Here, we aimed to test the corrosion potential of stents made of different materials in an in vitro setting. METHODS A total of 28 peripheral stents of different materials (nitinol, cobalt-chromium-nickel, tantalum, V4A) and surface treatments (electropolish, mechanical polish, no polish) were tested in vitro. Corrosion was accelerated by applying a constant voltage of 3.5 V and amperage of 1.16 mA in 0.9% NaCl. RESULTS Nitinol stents showed the lowest susceptibility to corrosion and the longest period without damage. The Memotherm II® (BARD Angiomed®) was the only stent that showed neither macroscopic nor microscopic damages. The worst performing material was cobalt-chromium-nickel, which showed corrosion damages about ten times earlier compared to nitinol. Considering the reasons for termination of the test, nitinol stents primarily showed length deficits, while V4A and tantalum stents showed fractures. Cobalt-chromium-nickel stents had multiple fractures or a complete lysis in equal proportions. When placed in direct contact, nitinol stents showed best corrosion resistance, regardless of what material they were combined with. In terms of polishing treatments, electropolished stents performed the best, mechanical-polished stents and those without polishing treatment followed. CONCLUSION The analysis of corrosion behavior may be useful to select the right stent fulfilling the individual needs of the patient within a large number of different stents. PMID:26268301

  5. Miniaturization Techniques for Accelerators

    SciTech Connect

    Spencer, James E.

    2003-05-27

    The possibility of laser driven accelerators [1] suggests the need for new structures based on micromachining and integrated circuit technology because of the comparable scales. Thus, we are exploring fully integrated structures including sources, optics (for both light and particle) and acceleration in a common format--an accelerator-on-chip (AOC). Tests suggest a number of preferred materials and techniques but no technical or fundamental roadblocks at scales of order 1 {micro}m or larger.

  6. Anticancer compound ABT-263 accelerates apoptosis in virus-infected cells and imbalances cytokine production and lowers survival rates of infected mice.

    PubMed

    Kakkola, L; Denisova, O V; Tynell, J; Viiliäinen, J; Ysenbaert, T; Matos, R C; Nagaraj, A; Ohman, T; Kuivanen, S; Paavilainen, H; Feng, L; Yadav, B; Julkunen, I; Vapalahti, O; Hukkanen, V; Stenman, J; Aittokallio, T; Verschuren, E W; Ojala, P M; Nyman, T; Saelens, X; Dzeyk, K; Kainov, D E

    2013-01-01

    ABT-263 and its structural analogues ABT-199 and ABT-737 inhibit B-cell lymphoma 2 (Bcl-2), BCL2L1 long isoform (Bcl-xL) and BCL2L2 (Bcl-w) proteins and promote cancer cell death. Here, we show that at non-cytotoxic concentrations, these small molecules accelerate the deaths of non-cancerous cells infected with influenza A virus (IAV) or other viruses. In particular, we demonstrate that ABT-263 altered Bcl-xL interactions with Bcl-2 antagonist of cell death (Bad), Bcl-2-associated X protein (Bax), uveal autoantigen with coiled-coil domains and ankyrin repeats protein (UACA). ABT-263 thereby activated the caspase-9-mediated mitochondria-initiated apoptosis pathway, which, together with the IAV-initiated caspase-8-mediated apoptosis pathway, triggered the deaths of IAV-infected cells. Our results also indicate that Bcl-xL, Bcl-2 and Bcl-w interact with pattern recognition receptors (PRRs) that sense virus constituents to regulate cellular apoptosis. Importantly, premature killing of IAV-infected cells by ABT-263 attenuated the production of key pro-inflammatory and antiviral cytokines. The imbalance in cytokine production was also observed in ABT-263-treated IAV-infected mice, which resulted in an inability of the immune system to clear the virus and eventually lowered the survival rates of infected animals. Thus, the results suggest that the chemical inhibition of Bcl-xL, Bcl-2 and Bcl-w could potentially be hazardous for cancer patients with viral infections. PMID:23887633

  7. Anticancer compound ABT-263 accelerates apoptosis in virus-infected cells and imbalances cytokine production and lowers survival rates of infected mice

    PubMed Central

    Kakkola, L; Denisova, O V; Tynell, J; Viiliäinen, J; Ysenbaert, T; Matos, R C; Nagaraj, A; Öhman, T; Kuivanen, S; Paavilainen, H; Feng, L; Yadav, B; Julkunen, I; Vapalahti, O; Hukkanen, V; Stenman, J; Aittokallio, T; Verschuren, E W; Ojala, P M; Nyman, T; Saelens, X; Dzeyk, K; Kainov, D E

    2013-01-01

    ABT-263 and its structural analogues ABT-199 and ABT-737 inhibit B-cell lymphoma 2 (Bcl-2), BCL2L1 long isoform (Bcl-xL) and BCL2L2 (Bcl-w) proteins and promote cancer cell death. Here, we show that at non-cytotoxic concentrations, these small molecules accelerate the deaths of non-cancerous cells infected with influenza A virus (IAV) or other viruses. In particular, we demonstrate that ABT-263 altered Bcl-xL interactions with Bcl-2 antagonist of cell death (Bad), Bcl-2-associated X protein (Bax), uveal autoantigen with coiled-coil domains and ankyrin repeats protein (UACA). ABT-263 thereby activated the caspase-9-mediated mitochondria-initiated apoptosis pathway, which, together with the IAV-initiated caspase-8-mediated apoptosis pathway, triggered the deaths of IAV-infected cells. Our results also indicate that Bcl-xL, Bcl-2 and Bcl-w interact with pattern recognition receptors (PRRs) that sense virus constituents to regulate cellular apoptosis. Importantly, premature killing of IAV-infected cells by ABT-263 attenuated the production of key pro-inflammatory and antiviral cytokines. The imbalance in cytokine production was also observed in ABT-263-treated IAV-infected mice, which resulted in an inability of the immune system to clear the virus and eventually lowered the survival rates of infected animals. Thus, the results suggest that the chemical inhibition of Bcl-xL, Bcl-2 and Bcl-w could potentially be hazardous for cancer patients with viral infections. PMID:23887633

  8. Optimal moderator materials at various proton energies considering photon dose rate after irradiation for an accelerator-driven ⁹Be(p, n) boron neutron capture therapy neutron source.

    PubMed

    Hashimoto, Y; Hiraga, F; Kiyanagi, Y

    2015-12-01

    We evaluated the accelerator beam power and the neutron-induced radioactivity of (9)Be(p, n) boron neutron capture therapy (BNCT) neutron sources having a MgF2, CaF2, or AlF3 moderator and driven by protons with energy from 8 MeV to 30 MeV. The optimal moderator materials were found to be MgF2 for proton energies less than 10 MeV because of lower required accelerator beam power and CaF2 for higher proton energies because of lower photon dose rate at the treatment position after neutron irradiation. PMID:26272165

  9. Comparing radiation dose rates in soils and riverine sediment to track the dispersion of radioactive contamination in Fukushima coastal rivers

    NASA Astrophysics Data System (ADS)

    Evrard, Olivier; Onda, Yuichi; Lepage, Hugo; Chartin, Caroline; Lefèvre, Irène; Cerdan, Olivier; Bonté, Philippe; Ayrault, Sophie

    2014-05-01

    The Fukushima Dai-ichi nuclear power plant (FDNPP) accident that occurred in March 2011 led to the formation of a 3000-km² radioactive pollution plume on soils located up to 70 km to the northwest of the damaged site. Forests and paddy fields are the dominant land uses in this mountainous region drained to the Pacific Ocean by several rivers that flow across densely inhabited coastal plains. It is then crucial to track the dispersion of radioactive material conveyed by those rivers to estimate the continental supply of radionuclides to the Ocean and to assess redistribution of radioactive sediment in those catchments. Radiations emitted by this contaminated material may indeed lead to an external exposure threat for local populations. As river discharge and sediment concentration data were not available during the first two years that followed the accident, alternative methods had to be developed to track this dispersion. We therefore organized field campaigns every six months and conducted local ground dose rate measurements to estimate whether fresh sediment drape deposits were more or less contaminated compared to local soils. Overall, our results showed that, in those regions exposed to violent typhoons and spring snowmelt, transfers of sediment are massive and episodic, and that they followed a seasonal cycle in 2011-2012. Then, in May 2013, contamination levels measured in sediment found in the upper parts of the catchments were almost systematically lower than the ones measured in nearby soils, whereas their contamination was higher in the coastal plains. This could have indicated a drying-up of the upstream sources of contamination. However, after the violent typhoons that occurred during summer in 2013, dose rates measured in fresh sediment deposits in November 2013 increased again systematically across the region. We thereby suggest that remobilization of contaminated sediment by typhoons and their storage in reservoirs and in coastal sections of the

  10. The Ability of Bispectral-Guided Management Compared to Routine Monitoring for Reflecting Awareness Rate in Patients Undergoing Abdominal Surgery

    PubMed Central

    Mozafari, Hamedeh; Asadi Fakhr, Amir; Salehi, Iraj; Moghimbigi, Abbas

    2014-01-01

    Background: Awareness during general anesthesia in different types of surgery is an important described adverse event. Bispectral (BIS) monitoring is one of the recent techniques proposed to monitor the depth of anesthesia. Objectives: The present study tested the hypothesis that the awareness rate and changes in hemodynamic parameters within anesthesia would be lower in patients allocated to BIS-guided management than those allocated to routine monitoring. Materials and Methods In total, 333 adult patients with the American Society of Anesthesiologists (ASA) physical status I-III, aged between 18 and 65 years scheduled for elective abdominal surgery under general anesthesia were included in this randomized double-blind placebo controlled trial. Patients were randomly allocated to BIS monitoring (n = 163) or routine monitoring (n = 170). BIS values and hemodynamic parameters including systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), and SPO2 were marked before induction (control value), after intubation and laryngoscopy, at intubation, after incision, and also during the operation every 15 minutes until extubation. Results: The overall incidence of awareness in the BIS and routine monitoring groups were 5.5% and 4.1%, which was not significantly different. There were no significant differences in hemodynamic indices including SBP, DBP, HR, and SPO2 before induction of anesthesia between the two groups. These between-group differences in the studied indices remained insignificant at different time points after anesthesia induction as well as post ICU hospitalization. Furthermore, the trend of changes in hemodynamic parameters was comparable in the two groups. Conclusions: BIS-guided management may not be superior to routine monitoring protocols to prevent awareness as well as hemodynamic changes during general anesthesia in patients undergoing abdominal surgeries. PMID:25593710

  11. Automated Peritoneal Dialysis Is Associated with Better Survival Rates Compared to Continuous Ambulatory Peritoneal Dialysis: A Propensity Score Matching Analysis

    PubMed Central

    Beduschi, Gabriela de Carvalho; Figueiredo, Ana Elizabeth; Olandoski, Marcia; Pecoits-Filho, Roberto; Barretti, Pasqual; de Moraes, Thyago Proenca

    2015-01-01

    Introduction The impact of peritoneal dialysis modality on patient survival and peritonitis rates is not fully understood, and no large-scale randomized clinical trial (RCT) is available. In the absence of a RCT, the use of an advanced matching procedure to reduce selection bias in large cohort studies may be the best approach. The aim of this study is to compare automated peritoneal dialysis (APD) and continuous ambulatory peritoneal dialysis (CAPD) according to peritonitis risk, technique failure and patient survival in a large nation-wide PD cohort Methods This is a prospective cohort study that included all incident PD patients with at least 90 days of PD recruited in the BRAZPD study. All patients who were treated exclusively with either APD or CAPD were matched for 15 different covariates using a propensity score calculated with the nearest neighbor method. Clinical outcomes analyzed were overall mortality, technique failure and time to first peritonitis. For all analysis we also adjusted the curves for the presence of competing risks with the Fine and Gray analysis. Results After the matching procedure, 2,890 patients were included in the analysis (1,445 in each group). Baseline characteristics were similar for all covariates including: age, diabetes, BMI, Center-experience, coronary artery disease, cancer, literacy, hypertension, race, previous HD, gender, pre-dialysis care, family income, peripheral artery disease and year of starting PD. Mortality rate was higher in CAPD patients (SHR1.44 CI95%1.21-1.71) compared to APD, but no difference was observed for technique failure (SHR0.83 CI95%0.69-1.02) nor for time till the first peritonitis episode (SHR0.96 CI95%0.93-1.11). Conclusion In the first large PD cohort study with groups balanced for several covariates using propensity score matching, PD modality was not associated with differences in neither time to first peritonitis nor in technique failure. Nevertheless, patient survival was significantly better

  12. Mortality, Recurrence, and Dependency Rates Are Higher after Acute Ischemic Stroke in Elderly Patients with Diabetes Compared to Younger Patients

    PubMed Central

    Long, Xue; Lou, Yongzhong; Gu, Hongfei; Guo, Xiaofei; Wang, Tao; Zhu, Yanxia; Zhao, Wenjuan; Ning, Xianjia; Li, Bin; Wang, Jinghua; An, Zhongping

    2016-01-01

    Stroke has a greater effect on the elderly than on younger patients. However, the long-term outcomes associated with stroke among elderly patients with diabetes are unknown. We aimed to assess the differences in long-term outcomes between young and elderly stroke patients with diabetes. A total of 3,615 acute ischemic stroke patients with diabetes were recruited for this study between 2006 and 2014. Outcomes at 12 and 36 months after stroke (including mortality, recurrence, and dependency) were compared between younger (age <75 years) and elderly (age ≥75 years) patients. The elderly group included 692 patients (19.1%) overall. Elderly patients were more likely than younger patients to have a Trial of Org 10172 in Acute Stroke Treatment classification of stroke due to cardioembolism, moderate and severe stroke, and atrial fibrillation, but less likely to have hypertension and dyslipidemia, current smokers, and alcohol consumers. Mortality, dependency, and recurrence rates at 12 months after stroke were 19.0, 48.5, and 20.9% in the elderly group and 7.4, 30.9, and 15.4% in the younger group, respectively (all P < 0.05). Corresponding rates at 36 months after stroke were 35.4, 78.7, and 53.8% in the elderly group and 13.7, 61.7, and 43.0% in the younger group, respectively (all P < 0.001). The mortality, dependency, and recurrence rates at 12 and 36 months after stroke were significantly higher in the elderly group than in the younger group after adjusting for stroke subtypes, stroke severity, and risk factors. Odds ratios (95% confidence interval) at 12 and 36 months after stroke were 2.18 (1.64–2.89) and 3.10 (2.35–4.08), respectively, for mortality, all P < 0.001; 1.81 (1.49–2.20) and 2.04 (1.57–2.34), respectively, for dependency, all P < 0.001; and 1.37 (1.06–1.76) and 1.40 (1.07–1.85), respectively, for recurrence, P = 0.016. The findings from this study suggest that management and secondary prevention should be emphasized in elderly patients with

  13. Mortality, Recurrence, and Dependency Rates Are Higher after Acute Ischemic Stroke in Elderly Patients with Diabetes Compared to Younger Patients.

    PubMed

    Long, Xue; Lou, Yongzhong; Gu, Hongfei; Guo, Xiaofei; Wang, Tao; Zhu, Yanxia; Zhao, Wenjuan; Ning, Xianjia; Li, Bin; Wang, Jinghua; An, Zhongping

    2016-01-01

    Stroke has a greater effect on the elderly than on younger patients. However, the long-term outcomes associated with stroke among elderly patients with diabetes are unknown. We aimed to assess the differences in long-term outcomes between young and elderly stroke patients with diabetes. A total of 3,615 acute ischemic stroke patients with diabetes were recruited for this study between 2006 and 2014. Outcomes at 12 and 36 months after stroke (including mortality, recurrence, and dependency) were compared between younger (age <75 years) and elderly (age ≥75 years) patients. The elderly group included 692 patients (19.1%) overall. Elderly patients were more likely than younger patients to have a Trial of Org 10172 in Acute Stroke Treatment classification of stroke due to cardioembolism, moderate and severe stroke, and atrial fibrillation, but less likely to have hypertension and dyslipidemia, current smokers, and alcohol consumers. Mortality, dependency, and recurrence rates at 12 months after stroke were 19.0, 48.5, and 20.9% in the elderly group and 7.4, 30.9, and 15.4% in the younger group, respectively (all P < 0.05). Corresponding rates at 36 months after stroke were 35.4, 78.7, and 53.8% in the elderly group and 13.7, 61.7, and 43.0% in the younger group, respectively (all P < 0.001). The mortality, dependency, and recurrence rates at 12 and 36 months after stroke were significantly higher in the elderly group than in the younger group after adjusting for stroke subtypes, stroke severity, and risk factors. Odds ratios (95% confidence interval) at 12 and 36 months after stroke were 2.18 (1.64-2.89) and 3.10 (2.35-4.08), respectively, for mortality, all P < 0.001; 1.81 (1.49-2.20) and 2.04 (1.57-2.34), respectively, for dependency, all P < 0.001; and 1.37 (1.06-1.76) and 1.40 (1.07-1.85), respectively, for recurrence, P = 0.016. The findings from this study suggest that management and secondary prevention should be emphasized in elderly patients with diabetes in

  14. A socio-hydrological comparative assessment explaining regional variances in suicide rate amongst farmers in Maharashtra, India

    NASA Astrophysics Data System (ADS)

    den Besten, Nadja I.; Pande, Saket; Savenije, Hubert H. G.

    2016-05-01

    Maharashtra is one of the states in India that has witnessed one of the highest rates of farmer suicides as proportion of total number of suicides. Most of the farmer suicides in Maharashtra are from semi-arid divisions such as Marathwada where cotton has been historically grown. Other dominant crops produced include cereals, pulses, oilseeds and sugarcane. Cotton (fibers), oilseeds and sugarcane providing highest value addition per unit cultivated area and cereals and pulses the least. Hence it is not surprising that smallholders take risks growing high value crops without "visualising" the risks it entails such as those corresponding to price and weather shocks.We deploy recently developed smallholder socio-hydrology modelling framework to understand the underlying dynamics of the crisis. It couples the dynamics of six main variables that are most relevant at the scale of a smallholder: water storage capacity (root zone storage and other ways of water storage), capital, livestock, soil fertility and fodder biomass. The hydroclimatic variability is accounted for at sub-annual scale and influences the socio-hydrology at annual scale. The model incorporates rule-based adaptation mechanisms (e.g., adjusting expenditures on food and fertilizers, selling livestocks) of smallholders when they face adverse conditions, such as high variability in rainfall or in agricultural prices. The model is applied to two adjoining divisions of Maharashtra: Marathwada and Desh. The former is the division with relatively higher farmer suicide rates than the latter. Diverse spatial data sets of precipitation, potential evaporation, soil, agricultural census based farm inputs, cropping pattern and prices are used to understand the dynamics of small farmers in these divisions, and to attribute farmer distress rates to soil types, hydroclimatic variability and crops grown.Comparative socio-hydrologic assessment across the two regions confirms existing narratives: low (soil) water storage

  15. 47 CFR 54.316 - Rate comparability review and certification for areas served by non-rural carriers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... COMMISSION (CONTINUED) COMMON CARRIER SERVICES (CONTINUED) UNIVERSAL SERVICE Universal Service Support for... Rates, Price Indices, and Expenditures for Telephone Service published by the Wireline Competition... Expenditures for Telephone Service. The Reference Book of Rates, Price Indices, and Expenditures for...

  16. Accelerated, Spleen-Based Titration of Variant Creutzfeldt-Jakob Disease Infectivity in Transgenic Mice Expressing Human Prion Protein with Sensitivity Comparable to That of Survival Time Bioassay

    PubMed Central

    Halliez, Sophie; Reine, Fabienne; Herzog, Laetitia; Jaumain, Emilie; Haïk, Stéphane; Rezaei, Human; Vilotte, Jean-Luc; Laude, Hubert

    2014-01-01

    ABSTRACT The dietary exposure of the human population to the prions responsible for the bovine spongiform encephalopathy (BSE) epizooty has led to the emergence of variant Creutzfeldt-Jakob disease (vCJD). This fatal, untreatable neurodegenerative disorder is a growing public health concern because the prevalence of the infection seems much greater than the disease incidence and because secondary transmission of vCJD by blood transfusion or use of blood products has occurred. A current limitation in variant CJD risk assessment is the lack of quantitative information on the infectivity of contaminated tissues. To address this limitation, we tested the potential of a transgenic mouse line overexpressing human prion protein (PrP), which was previously reported to propagate vCJD prions. Endpoint titration of vCJD infectivity in different tissues was evaluated by two different methods: (i) the “classical” bioassay, based on the appearance of clinical symptoms and the detection of pathological prion protein in tissues of the inoculated mouse, and (ii) a shortened bioassay based on the detection of the protein in the mouse spleen at defined time points. The two methods proved equally sensitive in quantifying infectivity, even after very-low-dose inoculation of infected material, but the time schedule was shortened from ∼2.5 years to ∼1 year with the spleen bioassay. Compared to the “gold-standard” RIII model routinely used for endpoint titration of vCJD/BSE prions, either method improved the sensitivity by >2 orders of magnitude and allowed reevaluating the infectious titer of spleen from a vCJD individual at disease end stage to >1,000-fold-higher values. IMPORTANCE Here, we provide key reevaluation of the infectious titer of variant CJD brain and spleen tissues. The highly sensitive, accelerated spleen-based assay should thus constitute a key advance for variant CJD epidemiological and risk assessment purposes and should greatly facilitate future titration

  17. Vehicle Efficiency and Tractive Work: Rate of Change for the Past Decade and Accelerated Progress Required for U.S. Fuel Economy and CO2 Regulations

    DOE PAGESBeta

    Thomas, John

    2016-04-05

    A major driving force for change in light-duty vehicle design and technology is the National Highway Traffic Safety Administration (NHTSA) and the U.S. Environmental Protection Agency (EPA) joint final rules concerning Corporate Average Fuel Economy (CAFE) and greenhouse gas (GHG) emissions for model years (MY) 2016 through 2025 passenger cars and light trucks. The chief goal of this current study is to compare the already rapid pace of fuel economy improvement and technological change over the previous decade to the needed rate of change to meet regulations over the next decade. EPA and NHTSA comparisons of the MY 2004 USmore » light-duty vehicle fleet to the MY 2014 fleet shows improved fuel economy (FE) of approximately 28% using the same FE estimating method mandated for CAFE regulations. Future predictions by EPA and NHTSA concerning ensemble fleet fuel economy are examined as an indicator of needed vehicle rate-of-change. A set of 40 same-model vehicle pairs for MY 2005 and MY 2015 is compared to examine changes in energy use and related technological change over the 10 year period. Powertrain improvements measured as increased vehicle efficiency, and vehicle mass-glider improvements measured as decreased tractive work requirements are quantified. The focus is first on conventional gasoline powertrain vehicles which currently dominate the market, with hybrids also examined due to their high potential importance for CAFE compliance. Most hybrid vehicles with significant sales in 2014 were represented in the study. Results show 10 years of progress for the studied vehicle set includes lowered tractive effort of about 5.6% and improved powertrain efficiency of about 16.5%. Further analysis shows that this high rate of past progress must increase by about 50% in order to meet the 2025 CAFE standards. Examination of where certain MY 2015 vehicle compare to CAFE regulations is offered as well as some simple conjecture on what is needed to meet regulations under

  18. Recreational Athletes Return to Sport at a Comparable Rate to Elite Athletes Following Hip Arthroscopy for Femoroacetabular Impingement

    PubMed Central

    Weber, Alexander E.; Kuhns, Benjamin; Cvetanovich, Gregory; Levy, David; Nho, Shane Jay

    2016-01-01

    on the recreational athlete and demonstrates comparable return-to-play rates while increasing the generalizability to the average sports medicine practice.

  19. Objective and Longitudinal Assessment of Dermatitis After Postoperative Accelerated Partial Breast Irradiation Using High-Dose-Rate Interstitial Brachytherapy in Patients With Breast Cancer Treated With Breast Conserving Therapy: Reduction of Moisture Deterioration by APBI

    SciTech Connect

    Tanaka, Eiichi; Yamazaki, Hideya; Yoshida, Ken; Takenaka, Tadashi; Masuda, Norikazu; Kotsuma, Tadayuki; Yoshioka, Yasuo; Inoue, Takehiro

    2011-11-15

    Purpose: To objectively evaluate the radiation dermatitis caused by accelerated partial breast irradiation (APBI) using high-dose-rate interstitial brachytherapy. Patients and Methods: The skin color and moisture changes were examined using a newly installed spectrophotometer and corneometer in 22 patients who had undergone APBI using open cavity implant high-dose-rate interstitial brachytherapy (36 Gy in six fractions) and compared with the corresponding values for 44 patients in an external beam radiotherapy (EBRT) control group (50-60 Gy in 25-30 fractions within 5-6 weeks) after breast conserving surgery. Results: All values changed significantly as a result of APBI. The extent of elevation in a Asterisk-Operator (reddish) and reduction in L Asterisk-Operator (black) values caused by APBI were similar to those for EBRT, with slightly delayed recovery for 6-12 months after treatment owing to the surgical procedure. In contrast, only APBI caused a change in the b Asterisk-Operator values, and EBRT did not, demonstrating that the reduction in b Asterisk-Operator values (yellowish) depends largely on the surgical procedure. The changes in moisture were less severe after APBI than after EBRT, and the recovery was more rapid. The toxicity assessment using the Common Toxicity Criteria, version 3, showed that all dermatitis caused by APBI was Grade 2 or less. Conclusion: An objective analysis can quantify the effects of APBI procedures on color and moisture cosmesis. The radiation dermatitis caused by APBI using the present schedule showed an equivalent effect on skin color and a less severe effect on moisture than the effects caused by standard EBRT.

  20. Sweat rate and fluid turnover in American football players compared with runners in a hot and humid environment

    PubMed Central

    Godek, S; Bartolozzi, A; Godek, J; Roberts, W

    2005-01-01

    Objectives: To determine sweat rate (SwR) and fluid requirements for American footballers practicing in a hot, humid environment compared with cross country runners in the same conditions. Methods: Fifteen subjects, 10 footballers and five runners, participated. On the 4th and 8th day of preseason two a day practices, SwR during exercise was determined in both morning and afternoon practices/runs from the change in body mass adjusted for fluids consumed and urine produced. Unpaired t tests were used to determine differences between groups. Results: Overall SwR measured in litres/h was higher in the footballers than the cross country runners (2.14 (0.53) v 1.77 (0.4); p<0.01). Total sweat loss in both morning (4.83 (1.2) v 1.56 (0.39) litres) and afternoon (4.8 (1.2) v 1.97 (0.28) litres) practices/runs, and daily sweat losses (9.4 (2.2) v 3.53 (0.54) litres) were higher in the footballers (p<0.0001). The footballers consumed larger volumes of fluid during both morning and afternoon practices/runs (23.9 (8.9) v 5.5 (3.1) ml/min and 23.5 (7.3) v 13.6 (5.6) ml/min; p<0.01). For complete hydration, the necessary daily fluid consumption calculated as 130% of daily sweat loss in the footballers was 12.2 (2.9) litres compared with 4.6 (0.7) litres in the runners (p<0.0001). Calculated 24 hour fluid requirements in the footballers ranged from 8.8 to 19 litres. Conclusions: The American footballers had a high SwR with large total daily sweat losses. Consuming large volumes of hypotonic fluid may promote sodium dilution. Recommendations for fluid and electrolyte replacement must be carefully considered and monitored in footballers to promote safe hydration and avoid hyponatraemia. PMID:15793087

  1. Heart rate and pulmonary function while wearing the launch-entry crew escape suit (LES) during + Gx acceleration and simulated Shuttle launch

    NASA Technical Reports Server (NTRS)

    Krutz, Robert W., Jr.; Bagian, James P.; Burton, Russell R.; Meeker, Larry J.

    1990-01-01

    Space shuttle crewmembers have been equipped with a launch-entry crew escape system (LES) since the Challenger accident in 1986. Some crewmembers, wearing the new pressure suit, have reported breathing difficulties and increased effort to achieve the desired range of motion. This study was conducted to quantify the reported increased physical workloads and breathing difficulty associated with wearing the LES. Both veteran astronauts and centrifuge panel members were exposed to various + Gx profiles (including simulated shuttle launch) + Gx on the USAF School of Aerospace Medicine (USAFSAM) human-use centrifuge. Maximum heart rate data showed no increased workload associated with arm and head movement in the LES when compared to the flight suit/helmet ensemble (LEH). However, the LES did impose a significant increase in breathing difficulty beginning at +2.5 Gx which was demonstrated by a decrease in forced vital capacity and subjected questionnaries.

  2. A high-fat diet containing lard accelerates prostate cancer progression and reduces survival rate in mice: possible contribution of adipose tissue-derived cytokines.

    PubMed

    Cho, Han Jin; Kwon, Gyoo Taik; Park, Heesook; Song, Hyerim; Lee, Ki Won; Kim, Jung-In; Park, Jung Han Yoon

    2015-04-01

    To examine the effects of high-fat diet (HFD) containing lard on prostate cancer development and progression and its underlying mechanisms, transgenic adenocarcinoma mouse prostate (TRAMP) and TRAMP-C2 allograft models, as well as in vitro culture models, were employed. In TRAMP mice, HFD feeding increased the incidence of poorly differentiated carcinoma and decreased that of prostatic intraepithelial neoplasia in the dorsolateral lobes of the prostate, which was accompanied by increased expression of proteins associated with proliferation and angiogenesis. HFD feeding also led to increased metastasis and decreased survival rate in TRAMP mice. In the allograft model, HFD increased solid tumor growth, the expression of proteins related to proliferation/angiogenesis, the number of lipid vacuoles in tumor tissues, and levels of several cytokines in serum and adipose tissue. In vitro results revealed that adipose tissue-conditioned media from HFD-fed mice stimulated the proliferation and migration of prostate cancer cells and angiogenesis compared to those from control-diet-fed mice. These results indicate that the increase of adipose tissue-derived soluble factors by HFD feeding plays a role in the growth and metastasis of prostate cancer via endocrine and paracrine mechanisms. These results provide evidence that a HFD containing lard increases prostate cancer development and progression, thereby reducing the survival rate. PMID:25912035

  3. 12 CFR 1501.3 - Comparable ratings requirement for national banks among the second 50 largest insured banks.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5136A(a)(2)(E) of the Revised Statutes (12 U.S.C. 24a) and 12 CFR 5.39(g)(3) if the bank has a current long-term issuer credit rating from at least one nationally recognized statistical rating organization...) Definition of long-term issuer credit rating. A “long-term issuer credit rating” is a written opinion...

  4. 12 CFR 1501.3 - Comparable ratings requirement for national banks among the second 50 largest insured banks.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5136A(a)(2)(E) of the Revised Statutes (12 U.S.C. 24a) and 12 CFR 5.39(g)(3) if the bank has a current long-term issuer credit rating from at least one nationally recognized statistical rating organization...) Definition of long-term issuer credit rating. A “long-term issuer credit rating” is a written opinion...

  5. 12 CFR 1501.3 - Comparable ratings requirement for national banks among the second 50 largest insured banks.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5136A(a)(2)(E) of the Revised Statutes (12 U.S.C. 24a) and 12 CFR 5.39(g)(3) if the bank has a current long-term issuer credit rating from at least one nationally recognized statistical rating organization...) Definition of long-term issuer credit rating. A “long-term issuer credit rating” is a written opinion...

  6. 12 CFR 1501.3 - Comparable ratings requirement for national banks among the second 50 largest insured banks.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5136A(a)(2)(E) of the Revised Statutes (12 U.S.C. 24a) and 12 CFR 5.39(g)(3) if the bank has a current long-term issuer credit rating from at least one nationally recognized statistical rating organization...) Definition of long-term issuer credit rating. A “long-term issuer credit rating” is a written opinion...

  7. 12 CFR 1501.3 - Comparable ratings requirement for national banks among the second 50 largest insured banks.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5136A(a)(2)(E) of the Revised Statutes (12 U.S.C. 24a) and 12 CFR 5.39(g)(3) if the bank has a current long-term issuer credit rating from at least one nationally recognized statistical rating organization...) Definition of long-term issuer credit rating. A “long-term issuer credit rating” is a written opinion...

  8. Comparability of the Social Skills Rating System to the Social Skills Improvement System: Content and Psychometric Comparisons across Elementary and Secondary Age Levels

    ERIC Educational Resources Information Center

    Gresham, Frank M.; Elliott, Stephen N.; Vance, Michael J.; Cook, Clayton R.

    2011-01-01

    This study compared the Social Skills Rating System (SSRS; Gresham & Elliott, 1990) with the revision of the SSRS, now called the Social Skills Improvement System-Rating Scales (SSIS-RS; Gresham & Elliott, 2008), across three raters (teacher, parent, and student) for elementary- and secondary-aged students. A detailed comparison of these two…

  9. Validation of the Spanish Center for Epidemiological Studies Depression and Zung Self-Rating Depression Scales: A Comparative Validation Study

    PubMed Central

    Arevalo, Jorge M.; Chavez, Kristhy; Vilela, Ana; Lazo, Maria; Huapaya, Julio

    2012-01-01

    Background Depressive disorders are leading contributors to burden of disease in developing countries. Research aiming to improve their diagnosis and treatment is fundamental in these settings, and psychometric tools are widely used instruments to support mental health research. Our aim is to validate and compare the psychometric properties of the Spanish versions of the Center for Epidemiological Studies Depression Scale (CES-D) and the Zung Self-Rating Depression Scale (ZSDS). Methodology/Principal Findings A Spanish version of the CES-D was revised by 5 native Spanish speaking psychiatrists using as reference the English version. A locally standardized Spanish version of the ZSDS was used. These Spanish versions were administered to 70 patients with a clinical diagnosis of DSM-IV Major Depressive Episode (MDE), 63 without major depression but with clinical diagnosis of other psychiatric disorders (OPD), and 61 with no evidence of psychiatric disorders (NEP). For both scales, Cronbach's alpha (C-α) and Hierarchical McDonald Omega for polychoric variables (MD-Ω) were estimated; and receiver operating characteristics (ROC) analysis performed. For the CES-D and ZSDS scales, C-α was 0.93 and 0.89 respectively, while MD-Ω was 0.90 and 0.75 respectively. The area under the ROC curve in MDE+OPD was 0.83 for CES-D and 0.84 for ZSDS; and in MDE+NEP was 0.98 for CES-D and 0.96 for ZSDS. Cut-off scores (co) for the highest proportions of correctly classified (cc) individuals among MDE+OPD were ≥29 for CES-D (sensitivity (ss) = 77.1/specificity (sp) = 79.4%/(cc) = 78.2%) and ≥47 for ZSDS (ss = 85.7%/sp = 71.4%/cc = 78.9%). In the MDE+NEP, co were ≥24 for the CES-D (ss = 91.4%/sp = 96.7%/cc = 93.9%) and ≥45 for the ZSDS (ss = 91.4%/sp = 91.8%/cc = 91.6%). Conclusion Spanish versions of the CES-D and ZSDS are valid instruments to detect depression in clinical settings and could be useful for both epidemiological

  10. Sinking rates of phytoplankton in the Changjiang (Yangtze River) estuary: A comparative study between Prorocentrum dentatum and Skeletonema dorhnii bloom

    NASA Astrophysics Data System (ADS)

    Guo, Shujin; Sun, Jun; Zhao, Qibiao; Feng, Yuanyuan; Huang, Daji; Liu, Sumei

    2016-02-01

    Sinking rates of phytoplankton community with variable taxonomic composition in the offshore Changjiang (Yangtze River) estuary were measured during two cruises in spring and summer, 2011. A homogenous-sample method SETCOL was used to determine the sinking rates. Phytoplankton community was dominated by dinoflagellates in spring and diatoms in summer, and two species Prorocentrum dentatum and Skeletonema dorhnii formed algal blooms in the survey area during the two cruises, respectively. Phytoplankton sinking rates ranged from 0.13 to 1.04 m day- 1 (average = 0.61 ± 0.24 m day- 1) in spring and 0.28 to 1.71 m day- 1 (average = 0.80 ± 0.34 m day- 1) in summer. In the surface layer, phytoplankton sinking rates at the P. dentatum bloom stations in spring were lower than that at the S. dorhnii bloom stations in summer. No significant correlation was found between phytoplankton sinking rates and most of the environmental parameters during the two cruises, except for temperature and nitrite concentration in summer. A significant correlation was observed between phytoplankton sinking rates and phytoplankton community structure in the surface layers: the higher dominance of diatom in the phytoplankton community corresponded to higher phytoplankton sinking rate. Therefore, the phytoplankton community structure other than the environmental parameters, is the important factor to affect the sinking rates greatly. The consequent carbon flux caused by phytoplankton sinking was estimated, and results suggested that the carbon flux to bottom water during the S. dorhnii bloom (average = 63.13 ± 48.16 mg C m- 2 day- 1) in summer was about 2.4 fold of that during the P. dentatum bloom (average = 26.10 ± 26.25 mg C m- 2 day- 1) in spring. These findings provide us some insight in understanding the carbon export contributed by marine phytoplankton in the coastal sea, where frequent phytoplankton blooms and high following carbon export occur.

  11. Statistical correlation of the soil incubation and the accelerated laboratory extraction methods to estimate nitrogen release rates of slow- and controlled-release fertilizers.

    PubMed

    Medina, L Carolina; Sartain, Jerry; Obreza, Thomas; Hall, William L; Thiex, Nancy J

    2014-01-01

    Several technologies have been proposed to characterize the nutrient release patterns of enhanced-efficiency fertilizers (EEFs) during the last few decades. These technologies have been developed mainly by manufacturers and are product-specific based on the regulation and analysis of each EEF product. Despite previous efforts to characterize nutrient release of slow-release fertilizer (SRF) and controlled-release fertilizer (CRF) materials, no official method exists to assess their nutrient release patterns. However, the increased production and distribution of EEFs in specialty and nonspecialty markets requires an appropriate method to verify nutrient claims and material performance. Nonlinear regression was used to establish a correlation between the data generated from a 180-day soil incubation-column leaching procedure and 74 h accelerated lab extraction method, and to develop a model that can predict the 180-day nitrogen (N) release curve for a specific SRF and CRF product based on the data from the accelerated laboratory extraction method. Based on the R2 > 0.90 obtained for most materials, results indicated that the data generated from the 74 h accelerated lab extraction method could be used to predict N release from the selected materials during 180 days, including those fertilizers that require biological activity for N release. PMID:25051612

  12. Comparing the effectiveness of heat rate improvements in different coal-fired power plants utilizing carbon dioxide capture

    NASA Astrophysics Data System (ADS)

    Walsh, Martin Jeremy

    New Congressional legislation may soon require coal-fired power generators to pay for their CO2 emissions and capture a minimum level of their CO2 output. Aminebased CO2 capture systems offer plants the most technically proven and commercially feasible option for CO2 capture at this time. However, these systems require a large amount of heat and power to operate. As a result, amine-based CO2 capture systems significantly reduce the net power of any units in which they are installed. The Energy Research Center has compiled a list of heat rate improvements that plant operators may implement before installing a CO2 capture system. The goal of these improvements is to upgrade the performance of existing units and partially offset the negative effects of adding a CO2 capture system. Analyses were performed in Aspen Plus to determine the effectiveness of these heat rate improvements in preserving the net power and net unit heat rate (NUHR) of four different power generator units. For the units firing high-moisture sub-bituminous coal, the heat rate improvements reduced NUHR by an average of 13.69% across a CO 2 capture level range of 50% to 90%. For the units firing bituminous coal across the same CO2 capture range, the heat rate improvements reduced NUHR by an average of 12.30%. Regardless of the units' coal or steam turbine cycle type, the heat rate improvements preserved 9.7% to 11.0% of each unit's net power across the same CO2 capture range. In general, the heat rate improvements were found to be most effective in improving the performance of units firing high-moisture sub-bituminous. The effect of the CO2 capture system on these units and the reasons for the improvements' greater effectiveness in them are described in this thesis.

  13. Marginal accuracy of nickel chromium copings fabricated by conventional and accelerated casting procedures, produced with ringless and metal ring investment procedures: A comparative in vitro study

    PubMed Central

    Alex, Deepa; Shetty, Y. Bharath; Miranda, Glynis Anita; Prabhu, M. Bharath; Karkera, Reshma

    2015-01-01

    Background: Conventional investing and casting techniques are time-consuming and usually requires 2–4 h for completion. Accelerated nonstandard, casting techniques have been reported to achieve similar quality results in significantly less time, namely, in 30–40 min. During casting, it is essential to achieve compensation for the shrinkage of solidifying alloy by investment expansion. The metal casting ring restricts the thermal expansion of investment because the thermal expansion of the ring is lesser than that of the investment. The use of casting ring was challenged with the introduction of the ringless technique. Materials and Methods: A total of 40 test samples of nickel chromium (Ni-Cr) cast copings were obtained from the patterns fabricated using inlay casting wax. The 20 wax patterns were invested using metal ring and 20 wax patterns were invested using the ringless investment system. Of both the groups, 10 samples underwent conventional casting, and the other 10 underwent accelerated casting. The patterns were casted using the induction casting technique. All the test samples of cast copings were evaluated for vertical marginal gaps at four points on the die employing a stereo optical microscope. Results: The vertical marginal discrepancy data obtained were tabulated. Mean and standard deviations were obtained. Vertical discrepancies were analyzed using analysis of variance and Tukey honestly significantly different. The data obtained were found to be very highly significant (P < 0.001). Mean vertical gap was the maximum for Group II (53.64 μm) followed by Group IV (47.62 μm), Group I (44.83 μm) and Group III (35.35 μm). Conclusion: The Ni-Cr cast copings fabricated with the conventional casting using ringless investment system showed significantly better marginal fit than that of cast copings fabricated from conventional and accelerated casting with metal ring investment and accelerated casting using ringless investment since those copings had

  14. Comparing rating paradigms for evidence-based program registers in behavioral health: evidentiary criteria and implications for assessing programs.

    PubMed

    Means, Stephanie N; Magura, Stephen; Burkhardt, Jason T; Schröter, Daniela C; Coryn, Chris L S

    2015-02-01

    Decision makers need timely and credible information about the effectiveness of behavioral health interventions. Online evidence-based program registers (EBPRs) have been developed to address this need. However, the methods by which these registers determine programs and practices as being “evidence-based” has not been investigated in detail. This paper examines the evidentiary criteria EBPRs use to rate programs and the implications for how different registers rate the same programs. Although the registers tend to employ a standard Campbellian hierarchy of evidence to assess evaluation results, there is also considerable disagreement among the registers about what constitutes an adequate research design and sufficient data for designating a program as evidence-based. Additionally, differences exist in how registers report findings of “no effect,” which may deprive users of important information. Of all programs on the 15 registers that rate individual programs, 79% appear on only one register. Among a random sample of 100 programs rated by more than one register, 42% were inconsistently rated by the multiple registers to some degree. PMID:25450778

  15. COMPARING RATING PARADIGMS FOR EVIDENCE-BASED PROGRAM REGISTERS IN BEHAVIORAL HEALTH: EVIDENTIARY CRITERIA AND IMPLICATIONS FOR ASSESSING PROGRAMS

    PubMed Central

    Means, Stephanie N.; Magura, Stephen; Burkhardt, Jason T.; Schröter, Daniela C.; Coryn, Chris L.S.

    2014-01-01

    Decision makers need timely and credible information about the effectiveness of behavioral health interventions. Online evidence-based program registers (EBPRs) have been developed to address this need. However, the methods by which these registers determine programs and practices as being “evidence-based” has not been investigated in detail. This paper examines the evidentiary criteria EBPRs use to rate programs and the implications for how different registers rate the same programs. Although the registers tend to employ a standard Campbellian hierarchy of evidence to assess evaluation results, there is also considerable disagreement among the registers about what constitutes an adequate research design and sufficient data for designating a program as evidence-based. Additionally, differences exist in how registers report findings of “no effect,” which may deprive users of important information. Of all programs on the 15 registers that rate individual programs, 79% appear on only one register. Among a random sample of 100 programs rated by more than one register, 42% were inconsistently rated by the multiple registers to some degree. PMID:25450778

  16. Comparative analysis of syntenic genes in grass genomes reveals accelerated rates of gene structure and coding sequence evolution in polyploid wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cycles of whole genome duplication (WGD) and diploidization are hallmarks of eukaryotic genome evolution and speciation. Polyploid wheat (Triticum aestivum) has had a massive increase in genome size largely due to recent WGDs. How these processes may impact the dynamics of gene evolution was studied...

  17. Accelerated Reader.

    ERIC Educational Resources Information Center

    Education Commission of the States, Denver, CO.

    This paper provides an overview of Accelerated Reader, a system of computerized testing and record-keeping that supplements the regular classroom reading program. Accelerated Reader's primary goal is to increase literature-based reading practice. The program offers a computer-aided reading comprehension and management program intended to motivate…

  18. Effects of changing from non-accelerated to accelerated MRI for follow-up in brain atrophy measurement.

    PubMed

    Leung, Kelvin K; Malone, Ian M; Ourselin, Sebastien; Gunter, Jeffrey L; Bernstein, Matt A; Thompson, Paul M; Jack, Clifford R; Weiner, Michael W; Fox, Nick C

    2015-02-15

    Stable MR acquisition is essential for reliable measurement of brain atrophy in longitudinal studies. One attractive recent advance in MRI is to speed up acquisition using parallel imaging (e.g. reducing volumetric T1-weighted acquisition scan times from around 9 to 5 min). In some studies, a decision to change to an accelerated acquisition may have been deliberately taken, while in others repeat scans may occasionally be accidentally acquired with an accelerated acquisition. In ADNI, non-accelerated and accelerated scans were acquired in the same scanning session on each individual. We investigated the impact on brain atrophy as measured by k-means normalized boundary shift integral (KN-BSI) and deformation-based morphometry when changing from non-accelerated to accelerated MRI acquisitions over a 12-month interval using scans of 422 subjects from ADNI. KN-BSIs were calculated using both a non-accelerated baseline scan and non-accelerated 12-month scans (i.e. consistent acquisition), and a non-accelerated baseline scan and an accelerated 12-month scan (i.e. changed acquisition). Fluid-based non-rigid registration was also performed on those scans to estimate the brain atrophy rate. We found that the effect on KN-BSI and fluid-based non-rigid registration depended on the scanner manufacturer. For KN-BSI, in Philips and Siemens scanners, the change had very little impact on the measured atrophy rate (increase of 0.051% in Philips and -0.035% in Siemens from consistent acquisition to changed acquisition), whereas, in GE, the change caused a mean reduction of 0.65% in the brain atrophy rate. This is likely due to the difference in tissue contrast between gray matter and cerebrospinal fluid in the non-accelerated and accelerated scans in GE, which uses IR-FSPGR instead of MP-RAGE. For fluid-based non-rigid registration, the change caused a mean increase of 0.29% in the brain atrophy rate in the changed acquisition compared with consistent acquisition in Philips

  19. Comparing the Rates of Early Childhood Victimization across Sexual Orientations: Heterosexual, Lesbian, Gay, Bisexual, and Mostly Heterosexual.

    PubMed

    Zou, Christopher; Andersen, Judith P

    2015-01-01

    Few studies have examined the rates of childhood victimization among individuals who identify as "mostly heterosexual" (MH) in comparison to other sexual orientation groups. For the present study, we utilized a more comprehensive assessment of adverse childhood experiences to extend prior literature by examining if MH individuals' experience of victimization more closely mirrors that of sexual minority individuals or heterosexuals. Heterosexual (n = 422) and LGB (n = 561) and MH (n = 120) participants were recruited online. Respondents completed surveys about their adverse childhood experiences, both maltreatment by adults (e.g., childhood physical, emotional, and sexual abuse and childhood household dysfunction) and peer victimization (i.e., verbal and physical bullying). Specifically, MH individuals were 1.47 times more likely than heterosexuals to report childhood victimization experiences perpetrated by adults. These elevated rates were similar to LGB individuals. Results suggest that rates of victimization of MH groups are more similar to the rates found among LGBs, and are significantly higher than heterosexual groups. Our results support prior research that indicates that an MH identity falls within the umbrella of a sexual minority, yet little is known about unique challenges that this group may face in comparison to other sexual minority groups. PMID:26444428

  20. Comparative Studies of the Density and Thermal Structure and Associated Escape Rates of Pluto and Triton's Atmospheres

    NASA Astrophysics Data System (ADS)

    Zhu, X.; Strobel, D. F.

    2015-12-01

    Both atmospheres of Pluto and Neptune's largest satellite Triton have cold surfaces with similar surface gravities and atmospheric surface pressures. We have updated the Zhu et al. Icarus 228, 301, 2014) model for Pluto's atmosphere by adopting Voigt line profiles in the radiation code with the latest spectral database and extended the model to Triton's atmosphere by including additional parameterized heating due to the magnetospheric electron energy deposition. Various numerical experiments have been conducted to investigate parameter sensitivities on the atmospheric escape rate for an icy planetary body similar to Pluto or Triton. It is found that the escape rate is sensitive to the planetary surface gravity due to a cumulative effect of the density variation with the altitude that significantly changes the atmospheric scale height at the exobase together with the exobase altitude. The atmospheric thermal structure near the exobase is sensitive to the atmospheric escape rate only when it is significantly greater than 1.0e26 molecules per second above which an enhanced escape rate induced by various diabatic energy sources leads to a stronger radial velocity that adiabatically cools the atmosphere to a lower temperature.

  1. Comparing the Rates of Early Childhood Victimization across Sexual Orientations: Heterosexual, Lesbian, Gay, Bisexual, and Mostly Heterosexual

    PubMed Central

    Zou, Christopher; Andersen, Judith P.

    2015-01-01

    Few studies have examined the rates of childhood victimization among individuals who identify as “mostly heterosexual” (MH) in comparison to other sexual orientation groups. For the present study, we utilized a more comprehensive assessment of adverse childhood experiences to extend prior literature by examining if MH individuals’ experience of victimization more closely mirrors that of sexual minority individuals or heterosexuals. Heterosexual (n = 422) and LGB (n = 561) and MH (n = 120) participants were recruited online. Respondents completed surveys about their adverse childhood experiences, both maltreatment by adults (e.g., childhood physical, emotional, and sexual abuse and childhood household dysfunction) and peer victimization (i.e., verbal and physical bullying). Specifically, MH individuals were 1.47 times more likely than heterosexuals to report childhood victimization experiences perpetrated by adults. These elevated rates were similar to LGB individuals. Results suggest that rates of victimization of MH groups are more similar to the rates found among LGBs, and are significantly higher than heterosexual groups. Our results support prior research that indicates that an MH identity falls within the umbrella of a sexual minority, yet little is known about unique challenges that this group may face in comparison to other sexual minority groups. PMID:26444428

  2. Inclusive Teachers' Concern and Rejection toward Their Students: Investigating the Validity of Ratings and Comparing Student Groups

    ERIC Educational Resources Information Center

    Cook, Bryan G.; Cameron, David L.

    2010-01-01

    This article reports two related studies. In the first study, concern and rejection ratings of 14 inclusive teachers toward 26 students with disabilities were correlated with teacher--student interactions. Partial correlations, controlling for severity of disability, indicated that instructional-academic interactions corresponded significantly…

  3. Prestige among Graduate and Professional Schools: Comparing the "U.S. News'" Graduate School Reputation Ratings between Disciplines

    ERIC Educational Resources Information Center

    Sweitzer, Kyle; Volkwein, J. Fredericks

    2009-01-01

    Using a conceptual model, this study examines the variables associated with the "U.S. News and World Report" peer assessment ratings of graduate and professional schools in business, education, engineering, law, and medicine. What are the correlates of prestige among the nation's leading graduate and professional schools, and are they consistent…

  4. Hydroxyl Radical Rate Constants: Comparing UV/H2O2 and Pulse Radiolysis for Environmental Pollutants

    EPA Science Inventory

    The objective of this study was to measure OH radical rates using both UV/H2O2 and pulse radiolysis techniques for 13 US EPA Contaminant Candidate List compounds (2,6- and 2,4-DNT, EPTC, prometon, linuron, diuron, dyfonate, diazinon, RDX, molinate, nitrobenz...

  5. Comparative Evaluation of the Effect of Menstruation, Pregnancy and Menopause on Salivary Flow Rate, pH and Gustatory Function

    PubMed Central

    Shetty, Vishwaprakash; Dave, Aparna; Arora, Manpreet; Hans, Vibha; Madan, Ajay

    2014-01-01

    Objective: There are five situations in a women’s life during which hormone fluctuations make them more susceptible to oral health problems – during puberty, at certain points in the monthly menstrual cycle, when using birth control pills, during pregnancy, and at menopause. The present study aimed at evaluating the effect of menstruation, pregnancy and menopause on salivary flow rate, pH and gustatory function. Materials and Methods: The study was carried out on 120 patients including 30 controls (with normal menstrual cycle of 28 to 30 d) and 90 cases (30 patients within three days of menstruation, 30 pregnant and 30 postmenopausal). Paraffin-stimulated saliva samples were obtained by expectoration to calculate salivary flow rate, pH was measured electrometically and patients were prospectively evaluated for gustatory function. Then, whole mouth taste test was performed in which the quality identification and intensity ratings of taste solutions were measured. Results: No statistically significant difference was found between the groups with respect to salivary flow rate but pH values were significantly lower in post menopausal women (p<0.05). Regarding correct quality identification the results were non-significant. Intensity for taste perception for sucrose was significantly lower in postmenopausal women than intensity of taste perception for other tastes (p<0.05). Also, postmenopausal women reported change in their dietary habits as all of them expressed liking for sweeter food. Conclusion: Reduced salivary flow rate and pH in postmen­opausal women may make them more prone to the occurrence of oral health problems. Also, pregnant and postmenopausal women appeared to have a reduced perception of sucrose, which can alter eating habits, such as intake of more sweet foods whereas no significant difference is observed in taste perception of NaCl, citric acid and quinine hydrochloride between the subjects. PMID:25478455

  6. Phase III trial comparing two low dose rates in brachytherapy of cervix carcinoma: Report at two years

    SciTech Connect

    Lambin, P.; Gerbaulet, A.; Kramer, A.; Haie-Meder, C.; Malaise, E.P.; Chassagne, D. ); Scalliet, P. )

    1993-02-15

    This Phase III randomized trial examined the effect of two low dose rates (0.73 or 0.38 Gy[center dot]h[sup [minus]1]) on the local control, survival, relapse-free survival, complications, and secondary effects in the treatment of cervical cancers. A total of 204 Stage Ib or II cervical carcinoma patients were included between January 1985 and September 1988. Treatment consisted of uterovaginal [sup 137]Cs irradiation followed by surgery. The two groups were similar for age, tumor stage and medical or surgical history. Their brachytherapy parameters were also similar (60 Gy pear dimensions, dose to critical organs, total kerma, etc....). There were no differences in the short-term effects or therapeutic outcome. However, overall complications and side effects observed after 6 months were significantly more frequent (p < 0.01) in the higher dose rate group. 40 refs., 4 figs., 6 tabs.

  7. Vertical hydraulic conductivity of a clayey-silt aquitard: accelerated fluid flow in a centrifuge permeameter compared with in situ conditions

    NASA Astrophysics Data System (ADS)

    Timms, W. A.; Crane, R.; Anderson, D. J.; Bouzalakos, S.; Whelan, M.; McGeeney, D.; Rahman, P. F.; Guinea, A.; Acworth, R. I.

    2014-03-01

    Evaluating the possibility of leakage through low permeability geological strata is critically important for sustainable water supplies, extraction of fuels from strata such as coal beds, and confinement of waste within the earth. Characterizing low or negligible flow rates and transport of solutes can require impractically long periods of field or laboratory testing, but is necessary for evaluations over regional areas and over multi-decadal timescales. The current work reports a custom designed centrifuge permeameter (CP) system, which can provide relatively rapid and reliable hydraulic conductivity (K) measurement compared to column permeameter tests at standard gravity (1g). Linear fluid velocity through a low K porous sample is linearly related to g-level during a CP flight unless consolidation or geochemical reactions occur. The CP module is designed to fit within a standard 2 m diameter, geotechnical centrifuge with a capacity for sample dimensions of 30 to 100 mm diameter and 30 to 200 mm in length. At maximum RPM the resultant centrifugal force is equivalent to 550g at base of sample or a total stress of ~2 MPa. K is calculated by measuring influent and effluent volumes. A custom designed mounting system allows minimal disturbance of drill core samples and a centrifugal force that represents realistic in situ stress conditions is applied. Formation fluids were used as influent to limit any shrink-swell phenomena which may alter the resultant K value. Vertical hydraulic conductivity (Kv) results from CP testing of core from the sites in the same clayey silt formation varied (10-7 to 10-9 m s-1, n = 14) but higher than 1g column permeameter tests of adjacent core using deionized water (10-9 to 10-11 m s-1, n = 7). Results at one site were similar to in situ Kv values (3 × 10-9 m s-1) from pore pressure responses within a 30 m clayey sequence in a homogenous area of the formation. Kv sensitivity to sample heterogeneity was observed, and anomalous flow via

  8. Comparing SSN Index to X-Ray Flare and Coronal Mass Ejection Rates from Solar Cycles 22 - 24

    NASA Astrophysics Data System (ADS)

    Winter, L. M.; Pernak, R. L.; Balasubramaniam, K. S.

    2016-05-01

    The newly revised sunspot-number series allows for placing historical geoeffective storms in the context of several hundred years of solar activity. Using statistical analyses of the Geostationary Operational Environmental Satellites (GOES) X-ray observations from the past {≈} 30 years and the Solar and Heliospheric Observatory (SOHO) Large Angle and Spectrometric Coronagraph (LASCO) Coronal Mass Ejection (CME) catalog (1996 - present), we present sunspot-number-dependent flare and CME rates. In particular, we present X-ray flare rates as a function of sunspot number for the past three cycles. We also show that the 1 - 8 Å X-ray background flux is strongly correlated with sunspot number across solar cycles. Similarly, we show that the CME properties (e.g. proxies related to the CME linear speed and width) are also correlated with sunspot number for Solar Cycles 23 and 24. These updated rates will enable future predictions for geoeffective events and place historical storms in the context of present solar activity.

  9. Evaluation of different partial AUCs as indirect measures of rate of drug absorption in comparative pharmacokinetic studies.

    PubMed

    Duquesnoy, C; Lacey, L F; Keene, O N; Bye, A

    1998-10-01

    The performance of different partial AUCs, including partial AUC from zero to t(max) of the reference formulation (AUC(r)) and partial AUC from zero to tmax of test or reference formulation, whichever occurs earliest (AUC(e), as indirect measures of rate of absorption have been evaluated using simulated experiments. The performance of these metrics relative to C(max), t(max) and C(max)/AUC(infinity) was further assessed using the results of actual studies involving a Glaxo drug. The normalised metrics AUC(r)/AUC(infinity) and AUC(e)/AUC(infinity) have also been evaluated. Our provisional conclusions were: (1) AUC(r)/AUC(infinity) and AUC(e)/AUC(infinity) had greater statistical power than C(max) and the non-normalised partial AUCs at detecting true differences in rate of absorption. Using real data, the performance of AUC(e)/AUC(infinity) was poor, however, the performance of AUC(r)/AUC(infinity) was good; (2) C(max)/AUC(infinity) was more precisely estimated than AUC(r)/AUC(infinity) or AUC(e)/AUC(infinity) and may be a superior metric for assessing absorption rates of highly variable drugs. PMID:9795077

  10. An investigation of the neutron flux in bone-fluorine phantoms comparing accelerator based in vivo neutron activation analysis and FLUKA simulation data

    NASA Astrophysics Data System (ADS)

    Mostafaei, F.; McNeill, F. E.; Chettle, D. R.; Matysiak, W.; Bhatia, C.; Prestwich, W. V.

    2015-01-01

    We have tested the Monte Carlo code FLUKA for its ability to assist in the development of a better system for the in vivo measurement of fluorine. We used it to create a neutron flux map of the inside of the in vivo neutron activation analysis irradiation cavity at the McMaster Accelerator Laboratory. The cavity is used in a system that has been developed for assessment of fluorine levels in the human hand. This study was undertaken to (i) assess the FLUKA code, (ii) find the optimal hand position inside the cavity and assess the effects on precision of a hand being in a non-optimal position and (iii) to determine the best location for our γ-ray detection system within the accelerator beam hall. Simulation estimates were performed using FLUKA. Experimental measurements of the neutron flux were performed using Mn wires. The activation of the wires was measured inside (1) an empty bottle, (2) a bottle containing water, (3) a bottle covered with cadmium and (4) a dry powder-based fluorine phantom. FLUKA was used to simulate the irradiation cavity, and used to estimate the neutron flux in different positions both inside, and external to, the cavity. The experimental results were found to be consistent with the Monte Carlo simulated neutron flux. Both experiment and simulation showed that there is an optimal position in the cavity, but that the effect on the thermal flux of a hand being in a non-optimal position is less than 20%, which will result in a less than 10% effect on the measurement precision. FLUKA appears to be a code that can be useful for modeling of this type of experimental system.

  11. LINEAR ACCELERATOR

    DOEpatents

    Colgate, S.A.

    1958-05-27

    An improvement is presented in linear accelerators for charged particles with respect to the stable focusing of the particle beam. The improvement consists of providing a radial electric field transverse to the accelerating electric fields and angularly introducing the beam of particles in the field. The results of the foregoing is to achieve a beam which spirals about the axis of the acceleration path. The combination of the electric fields and angular motion of the particles cooperate to provide a stable and focused particle beam.

  12. Mortality Rates in the General Irish Population Compared to Those with an Intellectual Disability from 2003 to 2012

    ERIC Educational Resources Information Center

    McCarron, Mary; Carroll, Rachael; Kelly, Caraiosa; McCallion, Philip

    2015-01-01

    Background:Historically, there has been higher and earlier mortality among people with intellectual disability as compared to the general population, but there have also been methodological problems and differences in the available studies. Method: Data were drawn from the 2012 National Intellectual Disability Database and the Census in Ireland. A…

  13. The Rating of Direct and Semi-Direct Oral Proficiency Interviews: Comparing Performance at Lower Proficiency Levels.

    ERIC Educational Resources Information Center

    Kenyon, Dorry M.; Tschirner, Erwin

    2000-01-01

    Reports on a study comparing student performances and test reliabilities for the German Speaking Test, a semi-direct tape-mediated oral proficiency test (GST) developed by the Center for Applied Linguistics, and the American Council on the Teaching of Foreign Languages Oral Proficiency Interviews. (Author/VWL)

  14. Low Stroke Rate of Carotid Stenosis Under the Guideline-Oriented Medical Treatment Compared With Surgical Treatment.

    PubMed

    Sato, Kimitoshi; Fujiyoshi, Kazuhiro; Hoshi, Keika; Noda, Chiharu; Yamaoka-Tojo, Minako; Ako, Junya; Kumabe, Toshihiro

    2016-01-01

    Medical treatment for asymptomatic carotid artery stenosis (ACAS) has advanced recently. The outcomes of medical treatment and surgical treatment were evaluated to clarify the optimal treatment for ACAS.Patients with ACAS of ≥ 50% luminal narrowing underwent serial follow-up carotid artery ultrasonography for one year or more at the Center for Cardiovascular Disease Prevention between November 2006 and October 2013. The incidence of cardiovascular events (stroke, myocardial infarction, cardiovascular death) was examined in 64 patients (medical treatment group), and in 47 patients (surgical group) who underwent surgical treatment (carotid endarterectomy or carotid artery stenting) during this same period at the Department of Neurosurgery.Annual cardiovascular event rate was 0.91% (2/219 person-year) in the group of guideline-oriented medical treatment with an annual check-up for disease management and 5.6% (6/107 person-year) in the surgical group (log-rank P = 0.027; HR in the medical treatment group, 0.19 [medical treatment/surgical]; 95% confidence interval [CI], 0.028 to 0.87). Annual stroke event rate was 0.46% (1/219 person-year) in the medical treatment group and 4.7% (5/107 personyear) in the surgical group (log-rank P = 0.016; HR in the medical treatment group, 0.11 [medical treatment/surgical]; 95% CI, 0.0057 to 0.70). Multivariate logistic analysis showed that the surgical group was an independent variable associated with cardiovascular events (P = 0.049).Annual cardiovascular and stroke event rates were low in patients receiving medical treatment for ACAS and better than surgical treatment. The present study shows that medical treatment is an important option for ACAS. PMID:26673440

  15. Pretreatment H2 receptor antagonists that differ in P450 modulation activity: comparative effects on paclitaxel clearance rates and neutropenia.

    PubMed

    Slichenmyer, W J; Donehower, R C; Chen, T L; Bowling, M K; McGuire, W P; Rowinsky, E K

    1995-01-01

    Histamine-2 receptor antagonists (H2RAs) are principal components of the premedication regimen used to prevent major hypersensitivity reactions in patients receiving paclitaxel. Several different H2RAs, including cimetidine, ranitidine and famotidine, have been used in clinical trials of paclitaxel, as well as by clinicians in different geographic regions and hospitals primarily because of differences in the availability of the various H2RAs. However, H2RAs have highly variable cytochrome P450-modulating capabilities, and the P450 system appears to play a major role in paclitaxel metabolism and disposition. Therefore, the use of different H2RAs may result in different pharmacologic, toxicologic and antitumor profiles due to differential effects on paclitaxel metabolism. This study evaluated whether cimetidine and famotidine, which possess disparate P450-modulating capabilities, differentially affect paclitaxel clearance rates and the agent's principal toxicity, neutropenia. Women with advanced, platinum-refractory ovarian carcinoma received two courses of treatment with 135 mg/m2 paclitaxel over 24 h while participating in the National Cancer Institute's Treatment Referral Center Protocol. A crossover design was employed in which consecutive patients received either 300 mg cimetidine i.v. or 20 mg famotidine i.v. before their first course of paclitaxel and the alternate H2RA before their second course. In order to evaluate the differential effects of cimetidine and famotidine on pertinent pharmacologic and toxicologic parameters in the same individual, paclitaxel concentrations at steady-state (Css), paclitaxel clearance rates, and absolute neutrophil counts (ANCs) were obtained during both courses. Paclitaxel Css values were not significantly different in individual patients when either cimetidine or famotidine preceded paclitaxel (p = 0.16). Mean paclitaxel clearance rates were 271 and 243 ml/min per m2 following cimetidine and famotidine, respectively. These

  16. Comparative evaluation of effect of complete denture wears on the flow rate of saliva in both medicated and apparently healthy patients

    PubMed Central

    Sonthalia, Abhay; Chandrasekaran, Arun P.; Mhaske, Sheetal P.; Lau, Mayank; Joshy, V. R.; Attokaran, George

    2016-01-01

    Aim and Objectives: In the denture wearing people, saliva is necessary to create adhesion, cohesion, and surface tension that ultimately leads to the increased retention of the denture. Medications have some influence on the flow rate of saliva and denture retention. The present study evaluates the effect of complete denture wear on the flow rate of saliva in both medicated and apparently healthy patients. Materials and Methods: The participants were 42 edentulous individuals aged 35–70 years requiring complete denture prostheses. The participants were divided into two groups of medicated and unmedicated. Unstimulated whole saliva was collected at 24 h and 3 months after the insertion of new complete dentures in both the groups. The data obtained were analyzed using Student's paired t-test and unpaired t-test. Intergroup changes were compared with unpaired t-test. Intragroup changes were compared with paired t-test using the Statistical Package for Social Sciences, version 22.0. Results: In the unmedicated group, the mean salivary flow rate was high at 24 h after denture insertion when compared to before denture insertion (P = 0.001 VHS). In the medicated group, the observation was highly significant (P = 0.007 HS) 24 h after denture insertion and after 3 months (P = 0.02 S) when compared to before denture insertion. Conclusion: No significant difference in the salivary flow rate was found 3 months after denture insertion when compared to before denture insertion for both the medicated and unmedicated groups. PMID:27382537

  17. Acceleration switch

    DOEpatents

    Abbin, J.P. Jr.; Devaney, H.F.; Hake, L.W.

    1979-08-29

    The disclosure relates to an improved integrating acceleration switch of the type having a mass suspended within a fluid filled chamber, with the motion of the mass initially opposed by a spring and subsequently not so opposed.

  18. Acceleration switch

    DOEpatents

    Abbin, Jr., Joseph P.; Devaney, Howard F.; Hake, Lewis W.

    1982-08-17

    The disclosure relates to an improved integrating acceleration switch of the type having a mass suspended within a fluid filled chamber, with the motion of the mass initially opposed by a spring and subsequently not so opposed.

  19. ION ACCELERATOR

    DOEpatents

    Bell, J.S.

    1959-09-15

    An arrangement for the drift tubes in a linear accelerator is described whereby each drift tube acts to shield the particles from the influence of the accelerating field and focuses the particles passing through the tube. In one embodiment the drift tube is splii longitudinally into quadrants supported along the axis of the accelerator by webs from a yoke, the quadrants. webs, and yoke being of magnetic material. A magnetic focusing action is produced by energizing a winding on each web to set up a magnetic field between adjacent quadrants. In the other embodiment the quadrants are electrically insulated from each other and have opposite polarity voltages on adjacent quadrants to provide an electric focusing fleld for the particles, with the quadrants spaced sufficienily close enough to shield the particles within the tube from the accelerating electric field.

  20. LINEAR ACCELERATOR

    DOEpatents

    Christofilos, N.C.; Polk, I.J.

    1959-02-17

    Improvements in linear particle accelerators are described. A drift tube system for a linear ion accelerator reduces gap capacity between adjacent drift tube ends. This is accomplished by reducing the ratio of the diameter of the drift tube to the diameter of the resonant cavity. Concentration of magnetic field intensity at the longitudinal midpoint of the external sunface of each drift tube is reduced by increasing the external drift tube diameter at the longitudinal center region.

  1. Biological Manipulation of Migration Rate: The Use of Advanced Photoperiod to Accelerate Smoltification in Yearling Chinook Salmon, Annual Report of Research 1990.

    SciTech Connect

    Muir, William D.

    1992-06-01

    Research was conducted during 1990 to assess the feasibility of biologically manipulating physiological development and migratory behavior of yearling spring chinook salmon, Oncorhynchus tshawytscha. At Dworshak National Fish Hatchery, one treatment group was exposed to a 3-month advanced photoperiod schedule for 13 weeks preceding release to accelerate smolt development. Another group was exposed to the same advanced photoperiod schedule, but additionally was reared at an elevated water temperature (11.9{degrees}C) for 10 days prior to release. At Leavenworth National Fish Hatchery, a treatment group was exposed to a 3-month advanced photoperiod schedule for 17 weeks. Gill Na{sup +}-K{sup +}ATPase development and migratory performance were described for all groups. The treated fish which were the most physiologically advanced at release were detected in the highest proportions at collector dams and also migrated fastest downstream--similar to results obtained in 1988 and 1989.

  2. Classifying fractionated electrograms in human atrial fibrillation using monophasic action potentials and activation mapping: Evidence for localized drivers, rate acceleration, and nonlocal signal etiologies

    PubMed Central

    Narayan, Sanjiv M.; Wright, Matthew; Derval, Nicolas; Jadidi, Amir; Forclaz, Andrei; Nault, Isabelle; Miyazaki, Shinsuke; Sacher, Frédéric; Bordachar, Pierre; Clémenty, Jacques; Jaïs, Pierre; Haïssaguerre, Michel; Hocini, Mélèze

    2011-01-01

    BACKGROUND Complex fractionated electrograms (CFAEs) detected during substrate mapping for atrial fibrillation (AF) reflect etiologies that are difficult to separate. Without knowledge of local refractoriness and activation sequence, CFAEs may represent rapid localized activity, disorganized wave collisions, or far-field electrograms. OBJECTIVE The purpose of this study was to separate CFAE types in human AF, using monophasic action potentials (MAPs) to map local refractoriness in AF and multipolar catheters to map activation sequence. METHODS MAP and adjacent activation sequences at 124 biatrial sites were studied in 18 patients prior to AF ablation (age 57 ± 13 years, left atrial diameter 45 ± 8 mm). AF cycle length, bipolar voltage, and spectral dominant frequency were measured to characterize types of CFAE. RESULTS CFAE were observed at 91 sites, most of which showed discrete MAPs and (1) pansystolic local activity (8%); (2) CFAE after AF acceleration, often with MAP alternans (8%); or (3) nonlocal (far-field) signals (67%). A fourth CFAE pattern lacked discrete MAPs (17%), consistent with spatial disorganization. CFAE with discrete MAPs and pansystolic activation (consistent with rapid localized AF sites) had shorter cycle length (P <.05) and lower voltage (P <.05) and trended to have higher dominant frequency than other CFAE sites. Many CFAEs, particularly at the septa and coronary sinus, represented far-field signals. CONCLUSION CFAEs in human AF represent distinct functional types that may be separated using MAPs and activation sequence. In a minority of cases, CFAEs indicate localized rapid AF sites. The majority of CFAEs reflect far-field signals, AF acceleration, or disorganization. These results may help to interpret CFAE during AF substrate mapping. PMID:20955820

  3. Benefits Gained, Benefits Lost: Comparing Baby Boomers to Other Generations in a Longitudinal Cohort Study of Self-Rated Health

    PubMed Central

    BADLEY, ELIZABETH M; CANIZARES, MAYILEE; PERRUCCIO, ANTHONY V; HOGG-JOHNSON, SHEILAH; GIGNAC, MONIQUE AM

    2015-01-01

    Policy Points Despite beliefs that baby boomers are healthier than previous generations, we found no evidence that the health of baby boomers is substantially different from that of the previous or succeeding cohorts. The effects of increased education, higher income, and lower smoking rates on improving self-rated health were nearly counterbalanced by the adverse effect of increasing body mass index (BMI). Assumptions that baby boomers will require less health care as they age because of better education, more prosperity, and less propensity to smoke may not be realized because of increases in obesity. Context Baby boomers are commonly believed to be healthier than the previous generation. Using self-rated health (SRH) as an indicator of health status, this study examines the effects of age, period, and birth cohort on the trajectory of health across 4 generations: World War II (born between 1935 and 1944), older baby boomers (born between 1945 and 1954), younger baby boomers (born between 1955 and 1964), and Generation X (born between 1965 and 1974). Methods We analyzed Canada’s longitudinal National Population Health Survey 1994-2010 (n = 8,570 at baseline), using multilevel growth models to estimate the age trajectory of SRH by cohort, accounting for period and incorporating the influence of changes in education, household income, smoking status, and body mass index (BMI) on SRH over time. Findings SRH worsened with increasing age in all cohorts. Cohort differences in SRH were modest (p = 0.034), but there was a significant period effect (p = 0.002). We found marked cohort effects for increasing education, income, and BMI, and decreasing smoking from the youngest to the oldest cohorts, which were much reduced (education and smoking) or removed (income and BMI) once period was taken into account. At the population level, multivariable analysis showed the benefits of increasing education and income and declines in smoking on the trajectory of improving SRH were

  4. Validation of estimated renal function measurements compared with the isotopic glomerular filtration rate in an HIV-infected cohort.

    PubMed

    Bonjoch, Anna; Bayés, Beatriz; Riba, Joaquim; Puig, Jordi; Estany, Carla; Perez-Alvarez, Núria; Clotet, Bonaventura; Negredo, Eugènia

    2010-12-01

    We performed a cross-sectional study to determine the best method for estimating the glomerular filtration rate (GFR) in HIV-infected subjects. Isotopic GFR was correlated with 24-h urine creatinine clearance, cystatin C levels, and 3 creatinine-based equations-the Modification of Diet in Renal Disease (MDRD), Cockcroft-Gault (CG), and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI)-in 15 patients. Cystatin C showed the strongest correlation with isotopic GFR (r=-0.760, p=0.001). When cystatin C was used as the reference variable for all 106 patients, CKD-EPI proved to be superior to the other equations (r=-0.671, p<0.001). Time with HIV infection, unsuppressed viral load, low CD4 T-cell counts, and use of protease inhibitors are related to an increased risk of renal impairment, leading us to recommend early initiation of antiretroviral therapy accompanied by a regular renal study. PMID:20887753

  5. Effect of the electron transport through thin slabs on the simulation of linear electron accelerators of use in therapy: A comparative study of various Monte Carlo codes

    NASA Astrophysics Data System (ADS)

    Vilches, M.; García-Pareja, S.; Guerrero, R.; Anguiano, M.; Lallena, A. M.

    2007-09-01

    When a therapeutic electron linear accelerator is simulated using a Monte Carlo (MC) code, the tuning of the initial spectra and the renormalization of dose (e.g., to maximum axial dose) constitute a common practice. As a result, very similar depth dose curves are obtained for different MC codes. However, if renormalization is turned off, the results obtained with the various codes disagree noticeably. The aim of this work is to investigate in detail the reasons of this disagreement. We have found that the observed differences are due to non-negligible differences in the angular scattering of the electron beam in very thin slabs of dense material (primary foil) and thick slabs of very low density material (air). To gain insight, the effects of the angular scattering models considered in various MC codes on the dose distribution in a water phantom are discussed using very simple geometrical configurations for the LINAC. The MC codes PENELOPE 2003, PENELOPE 2005, GEANT4, GEANT3, EGSnrc and MCNPX have been used.

  6. Comparative kill and growth rates determined with cefdinir and cefaclor and with Streptococcus pneumoniae and beta-lactamase-producing Haemophilus influenzae.

    PubMed Central

    Yourassowsky, E; Van der Linden, M P; Crokaert, F

    1992-01-01

    The relationship between the growth rate and the kill rate was used to evaluate and to compare the in vitro bactericidal activities of cefdinir, a new oral cephalosporin, and cefaclor against Streptococcus pneumoniae and beta-lactamase-producing strains of Haemophilus influenzae. These frequently encountered pathogens of community-acquired respiratory tract infections are usually susceptible to both drugs. The MIC ranges for cefdinir and cefaclor were, respectively, 0.03 to 0.06 and 0.25 to 0.5 micrograms/ml for S. pneumoniae and 0.25 and 4 to 8 micrograms/ml for H. influenzae. The colony counts (CFU per milliliter) measured after 6 h of exposure to a range of antibiotic concentrations in broth were plotted against the colony count of the control culture over the same period of time. Higher kill rates versus bacterial growth rates were noted for S. pneumoniae for both drugs (positive balance). Conversely, lower kill rates versus growth rates were noted for H. influenzae for both drugs (negative balance). In conclusion, the bactericidal activities of both drugs against S. pneumoniae and H. influenzae were similar when expressed by the relationship between the growth rate and the kill rate at 6 h, but cefdinir was more active at lower concentrations. PMID:1590698

  7. Comparative effectiveness of standard endotracheal tubes vs. endotracheal tubes with continuous subglottic suctioning on ventilator-associated pneumonia rates.

    PubMed

    Speroni, Karen Gabel; Lucas, Joy; Dugan, Lisa; O'Meara-Lett, Mildred; Putman, Marissa; Daniel, Marlon; Atherton, Martin

    2011-01-01

    Ventilator-associated pneumonia (VAP) accounts for the majority of nosocomial pneumonias, which may increase intensive care and prolonged hospital stays. Endotracheal tubes allowing continuous subglottic suctioning may reduce VAP; however, they are more expensive than standard endotracheal tubes not allowing continuous suctioning. he objective of this study was to measure the comparative costs associated with continuous subglottic suctioning endotracheal tubes (CSS-ETT) versus standard endotracheal tubes (S-ETT) among intubated patients and whether cost differential is offset by the occurrence of VAP in patients receiving either type of intubation. A retrospective chart review was conducted for 154 intubated adult patients (77 = S-ETT; 77 = CSS-ETT). The S-ETT group had one case of VAP; the CSS-ETT group had none. The mean total hospital charges were higher for the S-ETT group ($103,600; CSS-ETT= $88,500) (p = 0.3). Although the average number of intubation days and ICU days were greater for the CSS-ETT group, there were no cases of VAP compared to the S-ETT group. ased upon the one S-ETT VAP case and the VAP attributable costs, it is cost effective to use the CSS-ETT. PMID:21469484

  8. Accelerator vibration issues

    SciTech Connect

    Tennant, R.A.

    1985-01-01

    Vibrations induced in accelerator structures can cause particle-beam jitter and alignment difficulties. Sources of these vibrations may include pump oscillations, cooling-water turbulence, and vibrations transmitted through the floor to the accelerator structure. Drift tubes (DT) in a drift tube linac (DTL) are components likely to affect beam jitter and alignment because they normally have a heavy magnet structure on the end of a long and relatively small support stem. The natural vibrational frequencies of a drift tube have been compared with theoretical predictions. In principle, by knowing natural frequencies of accelerator components and system vibrational frequncies, an accelerator can be designed that does not have these frequencies coinciding. 2 refs., 2 figs., 2 tabs.

  9. A Comparative Study of USC (University of South Carolina) Student Survival Rates by Race, 1973-76. Research Notes 33-77.

    ERIC Educational Resources Information Center

    Fidler, Paul; Ponder, Eunice

    A study made at the University of South Carolina compared the survival (persistence) rates of full-time black and white students who entered the university as freshmen during the fall semesters of 1973, 1974, and 1975. Survival is defined as the percentage of students in an entering class who return for a second or subsequent years' enrollment at…

  10. Icodextrin does not impact infectious and culture-negative peritonitis rates in peritoneal dialysis patients: a 2-year multicentre, comparative, prospective cohort study

    PubMed Central

    Vychytil, Andreas; Remón, César; Michel, Catherine; Williams, Paul; Rodríguez-Carmona, Ana; Marrón, Belén; Vonesh, Ed; van der Heyden, Synke; Filho, Jose C. Divino

    2008-01-01

    Background. Icodextrin is a glucose polymer derived by hydrolysis of cornstarch. The different biocompatibility profile of icodextrin-containing peritoneal dialysis (PD) solutions may have a positive influence on peritoneal host defence. Furthermore, cases of sterile peritonitis potentially associated with icodextrin have been reported. Methods. The primary objective of this multicentre, longitudinal, observational, non-interventional, prospective cohort study, which included 722 PD patients, was to evaluate the incidence of overall peritonitis in patients treated with icodextrin-containing PD solutions (Extraneal™) used during one long-dwell exchange/day compared with those treated with non-icodextrin-containing PD solutions. The secondary objective was to determine if culture-negative peritonitis rates differed between patients treated with icodextrin from two independent manufacturers. All peritonitis episodes were assessed by a Steering Committee in a blind manner. Results. There was no significant difference between icodextrin-treated and control patients in the adjusted overall, culture-positive or culture-negative peritonitis rates. When stratified by the icodextrin supplier, there was no significant difference in the adjusted rate of culture-negative peritonitis episodes between groups. Conclusion. Subjects receiving icodextrin as part of their PD regimen experienced neither a higher rate of culture-negative peritonitis nor a lower rate of infectious peritonitis compared with non-icodextrin users. There was no significant influence of the icodextrin raw material supplier on peritonitis rates. PMID:18556747

  11. Comparative analysis between the floods and the rate of urbanization in the Ribeira Valley, São Paulo - Brazil

    NASA Astrophysics Data System (ADS)

    Ferreira, B. C.; Valverde, M. C.

    2013-05-01

    The aim of this paper is to analyze the occurrence of floods facing the rate of urbanization in the Ribeira Valley. The Ribeira Valley is located on the basin of Ribeira de Iguape River in eastern Paraná and southeastern São Paulo state in Brazil. The region has been considered one of the most important international conservation priorities by agencies such as the International Union for the Conservation of Nature (IUCN), and the UNESCO/MAB Program. This region has a history of recurrent floods, causing huge financial losses particularly to the poorest people, including casualties as well as material losses. This study analyzed three flood events that occurred in January 1995, January 1997 and February-March 1998, reaching the towns of Eldorado, Ribeira and Sete Barras. To determine the affected areas, the researchers used the shapes (digital data) obtained from the Geographic Information System of Ribeira de Iguape River Basin which is maintained by the Ribeira de Iguape River Basin and South Seashore Committee. The SPRING was the processing tool used for data manipulation. Additionally we used rainfall data, flow and water level elevation for the years 1983, 1995, 1997, 1998 and 2011. The results show that in January 1997 there happened the largest flood area across the three cities and this effect coincides with the highest levels of rainfall and flow. The second largest flood happened in January 1995 and the smallest one was in February-March 1998. Another important aspect to be noted is that all floods affected a large floodplain in both rural and urban areas. It was also found a direct relationship between the rate of urbanization and the area affected by the floods. The results show that the larger the area of urbanization, the larger the flooded area. It was also verified in the precipitation climatology that most extreme events occurred in 1983 and 2011. Specifically the 2011 event occurred during dry season bringing the whole region to a state of

  12. The presence of a dog attenuates cortisol and heart rate in the Trier Social Stress Test compared to human friends.

    PubMed

    Polheber, John P; Matchock, Robert L

    2014-10-01

    Limited research has addressed how social support in the form of a pet can affect both sympathetic and hypothalamic-pituitary-adrenal reactivity in response to a psychological challenge. The present study examined the effects of social support on salivary cortisol and heart rate (HR). Forty-eight participants were randomly assigned to three different conditions (human friend, novel dog, or control). All participants completed the Trier Social Stress Test and provided cortisol, HR, and State-Trait Anxiety Inventory measures. For participants paired with a dog, overall cortisol levels were attenuated throughout the experimental procedure, and HR was attenuated during the Trier Social Stress Test. For all groups, state anxiety increased after the Trier Social Stress Test, and HR during the Trier Social Stress Test was a predictor of cortisol. These results suggest that short-term exposure to a novel dog in an unfamiliar setting can be beneficial. They also suggest a possible mechanism for the beneficial effect associated with affiliation with pets. PMID:24170391

  13. Comparing delay discounting rates when using the fill-in-the-blank and multiple-choice methods.

    PubMed

    Weatherly, Jeffrey N; Derenne, Adam

    2011-01-01

    Several methods have been devised to measure delay discounting. The present study recruited university students to complete a delay-discounting task involving five different outcomes (finding a dating partner, free cigarettes, winning $100,000, being owed $100,000, and obtaining one's ideal body image) that was administered using either the fill-in-the blank (FITB) or multiple-choice (MC) method. Results showed that the different administration methods sometimes produced significantly different rates of discounting, the direction of which differed by outcome. Hyperbolic discounting and the area under the discounting curve were nearly always significantly correlated when the FITB method was used but were never significantly correlated when the MC method was used. Discounting across the five outcomes produced a two-factor solution when the FITB data were factor analyzed. The MC data were described by a one-factor solution. The present results illustrate that procedural variables have a potentially profound impact on delay-discounting data, and generalizing from studies on delay discounting should be done with caution until those variables are fully understood. PMID:24836568

  14. Comparing Subjective Ratings of Sexual Arousal and Desire in Partnered Sexual Activities from Women of Different Sexual Orientations.

    PubMed

    Persson, Tonje J; Ryder, Andrew G; Pfaus, James G

    2016-08-01

    Little is known about non-monosexual women's sexual arousal and desire. Typically, bisexual women have been excluded from research on sexual arousal and desire, whereas mostly heterosexual and mostly lesbian women have been placed into monosexual categories. This research (1) compared the subjective sexual arousal and desire of self-identified heterosexual, mostly heterosexual, bisexual, mostly lesbian, and lesbian women in partnered sexual activities with men and with women, and (2) compared within-group differences for subjective sexual arousal and desire with men versus women for the five groups. Participants included 388 women (M age = 24.40, SD = 6.40, 188 heterosexual, 53 mostly heterosexual, 64 bisexual, 32 mostly lesbian, 51 lesbian) who filled out the Sexual Arousal and Desire Inventory (SADI). Sexual orientation was associated with sexual arousal and desire in sexual activities with both men and with women. Bisexuals reported higher sexual arousal and desire for women than heterosexuals and lesbians, while lesbians reported lower sexual arousal and desire with men than the other groups. Heterosexuals and mostly heterosexuals scored higher on the male than on the female motivational dimension of the SADI, while the reverse was found for lesbians and mostly lesbians. Findings indicate that non-monosexuals have higher sexual arousal and desire in sexual activities with women than monosexuals. Further, bisexual women did not differentiate their sexual arousal with men versus women, while the other sexual orientation groups differentiated in terms of their motivation to engage in sexual activity. These findings may have implications for how female sexual orientation is conceptualized. PMID:25808718

  15. Gyro-induced acceleration of magnetic reconnection

    SciTech Connect

    Comisso, L.; Grasso, D.; Waelbroeck, F. L.; Borgogno, D.

    2013-09-15

    The linear and nonlinear evolution of magnetic reconnection in collisionless high-temperature plasmas with a strong guide field is analyzed on the basis of a two-dimensional gyrofluid model. The linear growth rate of the reconnecting instability is compared to analytical calculations over the whole spectrum of linearly unstable wave numbers. In the strongly unstable regime (large Δ′), the nonlinear evolution of the reconnecting instability is found to undergo two distinctive acceleration phases separated by a stall phase in which the instantaneous growth rate decreases. The first acceleration phase is caused by the formation of strong electric fields close to the X-point due to ion gyration, while the second acceleration phase is driven by the development of an open Petschek-like configuration due to both ion and electron temperature effects. Furthermore, the maximum instantaneous growth rate is found to increase dramatically over its linear value for decreasing diffusion layers. This is a consequence of the fact that the peak instantaneous growth rate becomes weakly dependent on the microscopic plasma parameters if the diffusion region thickness is sufficiently smaller than the equilibrium magnetic field scale length. When this condition is satisfied, the peak reconnection rate asymptotes to a constant value.

  16. Experimental test accelerator (ETA) II

    SciTech Connect

    Fessenden, T.J.; Atchison, W.L.; Birx, D.L.

    1981-03-06

    The Experimental Test Accelerator (ETA) is designed to produce a 10 kAmp electron beam at an energy of 4.5 MeV in 40 nsec pulses at an average rate of 2 pps. The accelerator also operates in bursts of 5 pulses spaced by as little as one millisec at an average rate of 5 pps. The machine is currently operating near 80% of its design values and has accumulated over 2.5 million pulses - mostly at a rate of one pps. The plasma cathode electron source, the remainder of the accelerator, and the operating characteristics of the machine are discussed.

  17. Accelerator on a Chip: How It Works

    SciTech Connect

    2014-06-30

    In an advance that could dramatically shrink particle accelerators for science and medicine, researchers used a laser to accelerate electrons at a rate 10 times higher than conventional technology in a nanostructured glass chip smaller than a grain of rice.

  18. Accelerator on a Chip: How It Works

    ScienceCinema

    None

    2014-07-16

    In an advance that could dramatically shrink particle accelerators for science and medicine, researchers used a laser to accelerate electrons at a rate 10 times higher than conventional technology in a nanostructured glass chip smaller than a grain of rice.

  19. Can reading rate acceleration improve error monitoring and cognitive abilities underlying reading in adolescents with reading difficulties and in typical readers?

    PubMed

    Horowitz-Kraus, Tzipi; Breznitz, Zvia

    2014-01-28

    Dyslexia is characterized by slow, inaccurate reading and by deficits in executive functions. The deficit in reading is exemplified by impaired error monitoring, which can be specifically shown through neuroimaging, in changes in Error-/Correct-related negativities (ERN/CRN). The current study aimed to investigate whether a reading intervention program (Reading Acceleration Program, or RAP) could improve overall reading, as well as error monitoring and other cognitive abilities underlying reading, in adolescents with reading difficulties. Participants with reading difficulties and typical readers were trained with the RAP for 8 weeks. Their reading and error monitoring were characterized both behaviorally and electrophysiologically through a lexical decision task. Behaviorally, the reading training improved "contextual reading speed" and decreased reading errors in both groups. Improvements were also seen in speed of processing, memory and visual screening. Electrophysiologically, ERN increased in both groups following training, but the increase was significantly greater in the participants with reading difficulties. Furthermore, an association between the improvement in reading speed and the change in difference between ERN and CRN amplitudes following training was seen in participants with reading difficulties. These results indicate that improving deficits in error monitoring and speed of processing are possible underlying mechanisms of the RAP intervention. We suggest that ERN is a good candidate for use as a measurement in evaluating the effect of reading training in typical and disabled readers. PMID:24316242

  20. How to assess and compare inter-rater reliability, agreement and correlation of ratings: an exemplary analysis of mother-father and parent-teacher expressive vocabulary rating pairs

    PubMed Central

    Stolarova, Margarita; Wolf, Corinna; Rinker, Tanja; Brielmann, Aenne

    2014-01-01

    This report has two main purposes. First, we combine well-known analytical approaches to conduct a comprehensive assessment of agreement and correlation of rating-pairs and to dis-entangle these often confused concepts, providing a best-practice example on concrete data and a tutorial for future reference. Second, we explore whether a screening questionnaire developed for use with parents can be reliably employed with daycare teachers when assessing early expressive vocabulary. A total of 53 vocabulary rating pairs (34 parent–teacher and 19 mother–father pairs) collected for two-year-old children (12 bilingual) are evaluated. First, inter-rater reliability both within and across subgroups is assessed using the intra-class correlation coefficient (ICC). Next, based on this analysis of reliability and on the test-retest reliability of the employed tool, inter-rater agreement is analyzed, magnitude and direction of rating differences are considered. Finally, Pearson correlation coefficients of standardized vocabulary scores are calculated and compared across subgroups. The results underline the necessity to distinguish between reliability measures, agreement and correlation. They also demonstrate the impact of the employed reliability on agreement evaluations. This study provides evidence that parent–teacher ratings of children's early vocabulary can achieve agreement and correlation comparable to those of mother–father ratings on the assessed vocabulary scale. Bilingualism of the evaluated child decreased the likelihood of raters' agreement. We conclude that future reports of agreement, correlation and reliability of ratings will benefit from better definition of terms and stricter methodological approaches. The methodological tutorial provided here holds the potential to increase comparability across empirical reports and can help improve research practices and knowledge transfer to educational and therapeutic settings. PMID:24994985

  1. Stochastic Particle Acceleration in Impulsive Solar Flares

    NASA Technical Reports Server (NTRS)

    Miller, James A.

    2001-01-01

    The acceleration of a huge number of electrons and ions to relativistic energies over timescales ranging from several seconds to several tens of seconds is the fundamental problem in high-energy solar physics. The cascading turbulence model we have developed has been shown previously (e.g., Miller 2000; Miller & Roberts 1995; Miner, LaRosa, & Moore 1996) to account for all the bulk features (such as acceleration timescales, fluxes, total number of energetic particles, and maximum energies) of electron and proton acceleration in impulsive solar flares. While the simulation of this acceleration process is involved, the essential idea of the model is quite simple, and consists of just a few parts: 1. During the primary flare energy release phase, we assume that low-amplitude MHD Alfven and fast mode waves are excited at long wavelengths, say comparable to the size of the event (although the results are actually insensitive to this initial wavelength). While an assumption, this appears reasonable in light of the likely highly turbulent nature of the flare. 2. These waves then cascade in a Kolmogorov-like fashion to smaller wavelengths (e.g., Verma et al. 1996), forming a power-law spectral density in wavenumber space through the inertial range. 3. When the mean wavenumber of the fast mode waves has increased sufficiently, the transit-time acceleration rate (Miller 1997) for superAlfvenic electrons can overcome Coulomb energy losses, and these electrons are accelerated out of the thermal distribution and to relativistic energies (Miller et al. 1996). As the Alfven waves cascade to higher wavenumbers, they can cyclotron resonate with progressively lower energy protons. Eventually, they will resonate with protons in the tail of the thermal distribution, which will then be accelerated to relativistic energies as well (Miller & Roberts 1995). Hence, both ions and electrons are stochastically accelerated, albeit by different mechanisms and different waves. 4. When the

  2. A Comparative Study of Survival Rate in High Grade Glioma Tumors Being Treated by Radiotherapy Alone Versus Chemoradiation With Nitrosourea

    PubMed Central

    Houshyari, Mohammad; Hajalikhani, Farzaneh; Rakhsha, Afshin; Hajian, Parastoo

    2015-01-01

    Background: In adults, malignant glioma (high-grade glioma) is one of the most common brain tumors. In spite of different types of treatment, the outcome is still not likely to be favorable. The aim of this study was to determine the difference between survival rate in adult patients with high grade glioma treated by radiotherapy only and those treated by a combination of radiotherapy and nitrosurea-based chemotherapy. Methods: This study was conducted using the records of 48 patients with grade 3 or 4 of glial brain tumor referred to the radiation-oncology ward of Shohada-e-Tajrish Hospital in Tehran, Iran from 2005 to 2012. The patients had undergone radiotherapy alone or adjuvant chemoradiation with nitrosourea. The median survival of patients after receiving the different types of treatment were evaluated using the Kaplan –Meier method and the log –rank exam. Data were analyzed using univariate analysis for median survival regarding to the patients’ age, gender, extent of surgery, Karnofsky performance status (KPS) with the Kaplan-Meier method, and the log-rank exam. We used the Cox-model for multivariate analysis. Results: Records of 48 patients were studied (34 men and 14 women). The mean survival were 18 months for men and 15.2 months for women (P = 0.05). Around 58% (28 patients) were more than 50 years old, and 42% (20 patients) were less than 50, and mean survival for the two age groups were 13 and 20 months, respectively (P < 0.001). Then, the patients were divided into three groups according to the extent of surgery, i.e., excisional biopsy (11 patients), stereotactic biopsy (22 patients), and resection (15 patients), and the mean survival for the three groups were 14.7, 17.3, and 18.8 months, respectively. There was no significant statistical difference for mean survival between the three groups (P = 0.23). The KPS was greater than 70% in 23 patients and less than 70% in 21 patients, and the mean survival for the former and latter groups were 17

  3. Comparative Analyses by Sequencing of Transcriptomes during Skeletal Muscle Development between Pig Breeds Differing in Muscle Growth Rate and Fatness

    PubMed Central

    Li, Anning; Gong, Wen; Xiao, Shuqi; Zhang, Yue; Qin, Limei; Niu, Yuna; Guo, Yunxue; Liu, Xiaohong; Cong, Peiqing; He, Zuyong; Wang, Chong; Li, Jiaqi; Chen, Yaosheng

    2011-01-01

    Understanding the dynamics of muscle transcriptome during development and between breeds differing in muscle growth is necessary to uncover the complex mechanism underlying muscle development. Herein, we present the first transcriptome-wide longissimus dorsi muscle development research concerning Lantang (LT, obese) and Landrace (LR, lean) pig breeds during 10 time-points from 35 days-post-coitus (dpc) to 180 days-post-natum (dpn) using Solexa/Illumina's Genome Analyzer. The data demonstrated that myogenesis was almost completed before 77 dpc, but the muscle phenotypes were still changed from 77 dpc to 28 dpn. Comparative analysis of the two breeds suggested that myogenesis started earlier but progressed more slowly in LT than in LR, the stages ranging from 49 dpc to 77 dpc are critical for formation of different muscle phenotypes. 595 differentially expressed myogenesis genes were identified, and their roles in myogenesis were discussed. Furthermore, GSK3B, IKBKB, ACVR1, ITGA and STMN1 might contribute to later myogenesis and more muscle fibers in LR than LT. Some myogenesis inhibitors (ID1, ID2, CABIN1, MSTN, SMAD4, CTNNA1, NOTCH2, GPC3 and HMOX1) were higher expressed in LT than in LR, which might contribute to more slow muscle differentiation in LT than in LR. We also identified several genes which might contribute to intramuscular adipose differentiation. Most important, we further proposed a novel model in which MyoD and MEF2A controls the balance between intramuscular adipogenesis and myogenesis by regulating CEBP family; Myf5 and MEF2C are essential during the whole myogenesis process while MEF2D affects muscle growth and maturation. The MRFs and MEF2 families are also critical for the phenotypic differences between the two pig breeds. Overall, this study contributes to elucidating the mechanism underlying muscle development, which could provide valuable information for pig meat quality improvement. The raw data have been submitted to Gene Expression

  4. Thomas Edison Accelerated Elementary School.

    ERIC Educational Resources Information Center

    Levin, Henry M.; Chasin, Gene

    This paper describes early outcomes of a Sacramento, California, elementary school that participated in the Accelerated Schools Project. The school, which serves many minority and poor students, began training for the project in 1992. Accelerated Schools were designed to advance the learning rate of students through a gifted and talented approach,…

  5. Suitable combination of promoter and micellar catalyst for kilo fold rate acceleration on benzaldehyde to benzoic acid conversion in aqueous media at room temperature: a kinetic approach.

    PubMed

    Ghosh, Aniruddha; Saha, Rumpa; Ghosh, Sumanta K; Mukherjee, Kakali; Saha, Bidyut

    2013-05-15

    The kinetics of oxidation of benzaldehyde by chromic acid in aqueous and aqueous surfactant (sodium dodecyl sulfate, SDS, alkyl phenyl polyethylene glycol, Triton X-100 and N-cetylpyridinium chloride, CPC) media have been investigated in the presence of promoter at 303 K. The pseudo-first-order rate constants (kobs) were determined from a logarithmic plot of absorbance as a function time. The rate constants were found to increase with introduction of heteroaromatic nitrogen base promoters such as Picolinic acid (PA), 2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen). The product benzoic acid has been characterized by conventional melting point experiment, NMR, HRMS and FTIR spectral analysis. The mechanism of both unpromoted and promoted reaction path has been proposed for the reaction. In presence of the anionic surfactant SDS, cationic surfactant CPC and neutral surfactant TX-100 the reaction can undergo simultaneously in both aqueous and micellar phase with an enhanced rate of oxidation in the micellar phase. Both SDS and TX-100 produce normal micellar effect whereas CPC produce reverse micellar effect in the presence of benzaldehyde. The observed net enhancement of rate effects has been explained by considering the hydrophobic and electrostatic interaction between the surfactants and reactants. SDS and bipy combination is the suitable one for benzaldehyde oxidation. PMID:23501718

  6. Suitable combination of promoter and micellar catalyst for kilo fold rate acceleration on benzaldehyde to benzoic acid conversion in aqueous media at room temperature: A kinetic approach

    NASA Astrophysics Data System (ADS)

    Ghosh, Aniruddha; Saha, Rumpa; Ghosh, Sumanta K.; Mukherjee, Kakali; Saha, Bidyut

    2013-05-01

    The kinetics of oxidation of benzaldehyde by chromic acid in aqueous and aqueous surfactant (sodium dodecyl sulfate, SDS, alkyl phenyl polyethylene glycol, Triton X-100 and N-cetylpyridinium chloride, CPC) media have been investigated in the presence of promoter at 303 K. The pseudo-first-order rate constants (kobs) were determined from a logarithmic plot of absorbance as a function time. The rate constants were found to increase with introduction of heteroaromatic nitrogen base promoters such as Picolinic acid (PA), 2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen). The product benzoic acid has been characterized by conventional melting point experiment, NMR, HRMS and FTIR spectral analysis. The mechanism of both unpromoted and promoted reaction path has been proposed for the reaction. In presence of the anionic surfactant SDS, cationic surfactant CPC and neutral surfactant TX-100 the reaction can undergo simultaneously in both aqueous and micellar phase with an enhanced rate of oxidation in the micellar phase. Both SDS and TX-100 produce normal micellar effect whereas CPC produce reverse micellar effect in the presence of benzaldehyde. The observed net enhancement of rate effects has been explained by considering the hydrophobic and electrostatic interaction between the surfactants and reactants. SDS and bipy combination is the suitable one for benzaldehyde oxidation.

  7. Acceleration Studies

    NASA Technical Reports Server (NTRS)

    Rogers, Melissa J. B.

    1993-01-01

    Work to support the NASA MSFC Acceleration Characterization and Analysis Project (ACAP) was performed. Four tasks (analysis development, analysis research, analysis documentation, and acceleration analysis) were addressed by parallel projects. Work concentrated on preparation for and implementation of near real-time SAMS data analysis during the USMP-1 mission. User support documents and case specific software documentation and tutorials were developed. Information and results were presented to microgravity users. ACAP computer facilities need to be fully implemented and networked, data resources must be cataloged and accessible, future microgravity missions must be coordinated, and continued Orbiter characterization is necessary.

  8. Comparative evaluation of rate of hydration and matrix erosion of HEC and HPC and study of drug release from their matrices.

    PubMed

    Sinha Roy, Dipasree; Rohera, Bhagwan D

    2002-08-01

    Hydrophilic polymers, in contact with the dissolution medium, may swell and make a continuous gel layer, erode or undergo combination of the two. The swelling action of these polymers is controlled by the rate of their hydration in the dissolution medium. The extent of polymer swelling, relative mobilities of dissolution medium and drug, and matrix erosion dictate the kinetics as well as mechanism of drug release from the polymeric matrices. The objective of the present investigations was to study the rate of hydration and the rate of matrix erosion of two hydrophilic, non-ionic cellulose ethers, i.e., hydroxyethylcellulose (HEC) and hydroxypropylcellulose (HPC), and to compare the kinetics and mechanism of drug release from their matrices. Chlorpheniramine maleate was used as the model drug. Matrix tablets containing chlorpheniramine maleate, HEC or HPC and dicalcium phosphate were compressed at 156 MPa pressure. The rate of hydration of the polymer, rate of erosion of the matrices and in vitro drug release studies were carried out in phosphate buffer (pH 7.4). The hydration studies of the two polymers demonstrated that due to relatively larger water uptake, the degree of swelling of HEC matrices was considerably higher as compared to the HPC matrices. Also, HEC matrices exhibited relatively higher erosion as compared to HPC matrices. The drug release from HEC matrices occurred by non-Fickian transport, i.e., combination of drug diffusion and polymer swelling, while drug release from HPC matrices was controlled primarily by diffusion through pores and channels in the structure. The t(50%), time to reach 50% drug release, for HEC matrices was 4.8 h and that for HPC matrices was 6.5 h which indicates that a higher polymer level was needed in the case of HEC matrices to sustain the drug release for up to 12 h of dissolution as compared to HPC matrices due to relatively higher hydrophilicity of HEC. PMID:12128174

  9. Preventing Australian football injuries with a targeted neuromuscular control exercise programme: comparative injury rates from a training intervention delivered in a clustered randomised controlled trial

    PubMed Central

    Twomey, Dara M; Fortington, Lauren V; Doyle, Tim L A; Elliott, Bruce C; Akram, Muhammad; Lloyd, David G

    2016-01-01

    Background Exercise-based training programmes are commonly used to prevent sports injuries but programme effectiveness within community men's team sport is largely unknown. Objective To present the intention-to-treat analysis of injury outcomes from a clustered randomised controlled trial in community Australian football. Methods Players from 18 male, non-elite, community Australian football clubs across two states were randomly allocated to either a neuromuscular control (NMC) (intervention n=679 players) or standard-practice (control n=885 players) exercise training programme delivered as part of regular team training sessions (2× weekly for 8-week preseason and 18-week regular-season). All game-related injuries and hours of game participation were recorded. Generalised estimating equations, adjusted for clustering (club unit), were used to compute injury incidence rates (IIRs) for all injuries, lower limb injuries (LLIs) and knee injuries sustained during games. The IIRs were compared across groups with cluster-adjusted Injury Rate Ratios (IRRs). Results Overall, 773 game injuries were recorded. The lower limb was the most frequent body region injured, accounting for 50% of injuries overall, 96 (12%) of which were knee injuries. The NMC players had a reduced LLI rate compared with control players (IRR: 0.78 (95% CI 0.56 to 1.08), p=0.14.) The knee IIR was also reduced for NMC compared with control players (IRR: 0.50 (95% CI 0.24 to 1.05), p=0.07). Conclusions These intention-to-treat results indicate that positive outcomes can be achieved from targeted training programmes for reducing knee and LLI injury rates in men's community sport. While not statistically significant, reducing the knee injury rate by 50% and the LLI rate by 22% is still a clinically important outcome. Further injury reductions could be achieved with improved training attendance and participation in the programme. PMID:26399611

  10. Probiotic supplementation does not improve eradication rate of Helicobacter pylori infection compared to placebo based on standard therapy: a meta-analysis

    PubMed Central

    Lu, Chao; Sang, Jianzhong; He, Haijian; Wan, Xingyong; Lin, Yiming; Li, Lan; Li, Youming; Yu, Chaohui

    2016-01-01

    This meta-analysis included eligible randomized controlled trials (RCTs) with the aim of determining whether probiotic supplementation can improve H. pylori eradication rates. PUBMED, EBSCO, Web of Science, and Ovid databases were searched. We included RCTs that investigated the effect of combining probiotics, with or without a placebo, with standard therapy. A total of 21 RCTs that reported standard therapy plus probiotics were included. Compared to the placebo group, the probiotics group was 1.21(OR 1.21, 95% CI: 0.86, 1.69) and 1.28 (OR 1.28, 95% CI: 0.88, 1.86) times more likely to achieve eradication of H. pylori infection in intent-to-treat (ITT) analysis and per protocol (PP) analysis, respectively. Probiotics with triple therapy plus a 14-day course of treatment did not improve the eradication of H. pylori infection (OR 1.44, 95% CI: 0.87, 2.39) compared to the placebo. Moreover, the placebo plus standard therapy did not improve eradication rates compared to standard therapy alone (P = 0.816). However, probiotics did improve the adverse effects of diarrhea and nausea. These pooled data suggest that the use of probiotics plus standard therapy does not improve the eradication rate of H. pylori infection compared to the placebo. PMID:26997149

  11. Plasma Wakefield Acceleration and FACET - Facilities for Accelerator Science and Experimental Test Beams at SLAC

    ScienceCinema

    Andrei Seryi

    2010-01-08

    Plasma wakefield acceleration is one of the most promising approaches to advancing accelerator technology. This approach offers a potential 1,000-fold or more increase in acceleration over a given distance, compared to existing accelerators.  FACET, enabled by the Recovery Act funds, will study plasma acceleration, using short, intense pulses of electrons and positrons. In this lecture, the physics of plasma acceleration and features of FACET will be presented.  

  12. Plasma Wakefield Acceleration and FACET - Facilities for Accelerator Science and Experimental Test Beams at SLAC

    SciTech Connect

    Andrei Seryi

    2009-09-09

    Plasma wakefield acceleration is one of the most promising approaches to advancing accelerator technology. This approach offers a potential 1,000-fold or more increase in acceleration over a given distance, compared to existing accelerators.  FACET, enabled by the Recovery Act funds, will study plasma acceleration, using short, intense pulses of electrons and positrons. In this lecture, the physics of plasma acceleration and features of FACET will be presented.  

  13. Accelerated molecular dynamics methods

    SciTech Connect

    Perez, Danny

    2011-01-04

    The molecular dynamics method, although extremely powerful for materials simulations, is limited to times scales of roughly one microsecond or less. On longer time scales, dynamical evolution typically consists of infrequent events, which are usually activated processes. This course is focused on understanding infrequent-event dynamics, on methods for characterizing infrequent-event mechanisms and rate constants, and on methods for simulating long time scales in infrequent-event systems, emphasizing the recently developed accelerated molecular dynamics methods (hyperdynamics, parallel replica dynamics, and temperature accelerated dynamics). Some familiarity with basic statistical mechanics and molecular dynamics methods will be assumed.

  14. Body acceleration distribution and O2 uptake in humans during running and jumping

    NASA Technical Reports Server (NTRS)

    Bhattacharya, A.; Mccutcheon, E. P.; Shvartz, E.; Greenleaf, J. E.

    1980-01-01

    The distribution of body acceleration and associated oxygen uptake and heart rate responses are investigated in treadmill running and trampoline jumping. Accelerations in the +Gz direction were measured at the lateral ankle, lumbosacral region and forehead of eight young men during level treadmill walking and running at four speeds and trampoline jumping at four heights, together with corresponding oxygen uptake and heart rate. With increasing treadmill speed, peak acceleration at the ankle is found always to exceed that at the back and forehead, and acceleration profiles with higher frequency components than those observed during jumping are observed. Acceleration levels are found to be more uniformly distributed with increasing height in jumping, although comparable oxygen uptake and heat rates are obtained. Results indicate that the magnitude of the biomechanical stimuli is greater in trampoline jumping than in running, which finding could be of use in the design of procedures to avert deconditioning in persons exposed to weightlessness.

  15. [A model-based meta-analysis to compare urate-lowering response rate of febuxostat and allopurinol in gout patient].

    PubMed

    Sun, Yi; Li, Liang; Zhou, Tian-Yan; Lu, Wei

    2014-12-01

    This study aims to compare the urate-lowering response rate of febuxostat and allopurinol in gout patient using a model-based meta-analysis. The literature search identified 22 clinical trials of gout with a total of 43 unique treatment arms that met our inclusion criteria, and a total of 6 365 gout patients were included in the study. The response rates of allopuriol and febuxostat were characterized by Tmax model and Emax model respectively, and the effect of baseline serum uric acid (sUA) and patient type on the drug effect was tested. The results showed that allopurinol can reach an average maximum response rate of 50.8% while febuxostat can reach a 100% response rate within a very short time, and the ED50 was 34.3 mg. Covariate analysis revealed that baseline sUA has a negative effect on response rate of allopurinol, and a positive effect on the predicted ED50 of febuxostat. For patients who had shown inadequate response to prior allopurinol treatment, the average response rate was about half that of the allopurinol responder patients. PMID:25920196

  16. Plasma accelerator

    DOEpatents

    Wang, Zhehui; Barnes, Cris W.

    2002-01-01

    There has been invented an apparatus for acceleration of a plasma having coaxially positioned, constant diameter, cylindrical electrodes which are modified to converge (for a positive polarity inner electrode and a negatively charged outer electrode) at the plasma output end of the annulus between the electrodes to achieve improved particle flux per unit of power.

  17. Accelerated Achievement

    ERIC Educational Resources Information Center

    Ford, William J.

    2010-01-01

    This article focuses on the accelerated associate degree program at Ivy Tech Community College (Indiana) in which low-income students will receive an associate degree in one year. The three-year pilot program is funded by a $2.3 million grant from the Lumina Foundation for Education in Indianapolis and a $270,000 grant from the Indiana Commission…

  18. ACCELERATION INTEGRATOR

    DOEpatents

    Pope, K.E.

    1958-01-01

    This patent relates to an improved acceleration integrator and more particularly to apparatus of this nature which is gyrostabilized. The device may be used to sense the attainment by an airborne vehicle of a predetermined velocitv or distance along a given vector path. In its broad aspects, the acceleration integrator utilizes a magnetized element rotatable driven by a synchronous motor and having a cylin drical flux gap and a restrained eddy- current drag cap deposed to move into the gap. The angular velocity imparted to the rotatable cap shaft is transmitted in a positive manner to the magnetized element through a servo feedback loop. The resultant angular velocity of tae cap is proportional to the acceleration of the housing in this manner and means may be used to measure the velocity and operate switches at a pre-set magnitude. To make the above-described dcvice sensitive to acceleration in only one direction the magnetized element forms the spinning inertia element of a free gyroscope, and the outer housing functions as a gimbal of a gyroscope.

  19. Particle acceleration

    NASA Technical Reports Server (NTRS)

    Vlahos, L.; Machado, M. E.; Ramaty, R.; Murphy, R. J.; Alissandrakis, C.; Bai, T.; Batchelor, D.; Benz, A. O.; Chupp, E.; Ellison, D.

    1986-01-01

    Data is compiled from Solar Maximum Mission and Hinothori satellites, particle detectors in several satellites, ground based instruments, and balloon flights in order to answer fundamental questions relating to: (1) the requirements for the coronal magnetic field structure in the vicinity of the energization source; (2) the height (above the photosphere) of the energization source; (3) the time of energization; (4) transistion between coronal heating and flares; (5) evidence for purely thermal, purely nonthermal and hybrid type flares; (6) the time characteristics of the energization source; (7) whether every flare accelerates protons; (8) the location of the interaction site of the ions and relativistic electrons; (9) the energy spectra for ions and relativistic electrons; (10) the relationship between particles at the Sun and interplanetary space; (11) evidence for more than one acceleration mechanism; (12) whether there is single mechanism that will accelerate particles to all energies and also heat the plasma; and (13) how fast the existing mechanisms accelerate electrons up to several MeV and ions to 1 GeV.

  20. Authors attain comparable or slightly higher rates of citation publishing in an open access journal (CytoJournal) compared to traditional cytopathology journals - A five year (2007-2011) experience

    PubMed Central

    Frisch, Nora K.; Nathan, Romil; Ahmed, Yasin K.; Shidham, Vinod B.

    2014-01-01

    Background: The era of Open Access (OA) publication, a platform which serves to better disseminate scientific knowledge, is upon us, as more OA journals are in existence than ever before. The idea that peer-reviewed OA publication leads to higher rates of citation has been put forth and shown to be true in several publications. This is a significant benefit to authors and is in addition to another relatively less obvious but highly critical component of the OA charter, i.e. retention of the copyright by the authors in the public domain. In this study, we analyzed the citation rates of OA and traditional non-OA publications specifically for authors in the field of cytopathology. Design: We compared the citation patterns for authors who had published in both OA and traditional non-OA peer-reviewed, scientific, cytopathology journals. Citations in an OA publication (CytoJournal) were analyzed comparatively with traditional non-OA cytopathology journals (Acta Cytologica, Cancer Cytopathology, Cytopathology, and Diagnostic Cytopathology) using the data from web of science citation analysis site (based on which the impact factors (IF) are calculated). After comparing citations per publication, as well as a time adjusted citation quotient (which takes into account the time since publication), we also analyzed the statistics after excluding the data for meeting abstracts. Results: Total 28 authors published 314 publications as articles and meeting abstracts (25 authors after excluding the abstracts). The rate of citation and time adjusted citation quotient were higher for OA in the group where abstracts were included (P < 0.05 for both). The rates were also slightly higher for OA than non-OA when the meeting abstracts were excluded, but the difference was statistically insignificant (P = 0.57 and P = 0.45). Conclusion We observed that for the same author, the publications in the OA journal attained a higher rate of citation than the publications in the traditional non

  1. Accelerated testing of space batteries

    NASA Technical Reports Server (NTRS)

    Mccallum, J.; Thomas, R. E.; Waite, J. H.

    1973-01-01

    An accelerated life test program for space batteries is presented that fully satisfies empirical, statistical, and physical criteria for validity. The program includes thermal and other nonmechanical stress analyses as well as mechanical stress, strain, and rate of strain measurements.

  2. Use of circumsporozoite protein enzyme-linked immunosorbent assay compared with microscopic examination of salivary glands for calculation of malaria infectivity rates in mosquitoes (Diptera: Culicidae) from Cameroon.

    PubMed

    Fontenille, D; Meunier, J Y; Nkondjio, C A; Tchuinkam, T

    2001-05-01

    A survey in Cameroon compared the usefulness of the circumsporozoite protein enzyme-linked immunosorbent assay (CSP ELISA) to dissection and microscopic examination of anopheline salivary glands for measuring infectivity rates in anopheline mosquitoes. The salivary glands of 375 females, belonging to four species were examined for sporozoites. After microscopic examination, the glands as well as all the remaining heads and thoraces were tested by ELISA. The sensitivity of ELISA was 100% (18/18), confidence interval (CI) (78.1-100) and the specificity was 99.7% (357/358), CI (98.2 100). The Kappa value, agreement between examination of the glands and salivary gland ELISA, was 0.97. The head thorax CSP ELISA overestimated the true salivary gland infection rate by 12.0%. The results obtained in Central Africa in a village with perennial transmission highly justified the use of the ELISA for measuring the entomological inoculation rate. PMID:11372973

  3. Acoustic particle acceleration sensors

    SciTech Connect

    Franklin, J.B.; Barry, P.J.

    1996-04-01

    A crossed dipole array provides a directional receiving capability in a relatively small sensor package and is therefore very attractive for many applications in acoustics. Particle velocity measurements on two axes perpendicular to each other are required to provide the dipole signals. These can be obtained directly using particle velocity sensors or via simple transfer functions using acceleration and displacement sensors. Also, the derivative of the acoustic pressure with respect to space provides a signal proportional to the particle acceleration and gives rise to the pressure gradient sensor. Each of these sensors has strengths and drawbacks depending on the frequency regime of interest, the noise background, and whether a point or a line configuration of dipole sensors is desired. In this paper, the performance of acceleration sensors is addressed using a sensor concept developed at DREA. These sensors exploit bending stresses in a cantilever beam of piezoelectric material to obtain wide bandwidth and high sensitivity. Models which predict the acceleration sensitivity, pressure sensitivity, and natural frequency for this type of sensor are described. Experimental results obtained using several different versions of these sensors are presented and compared with theory. The predicted performance of acceleration sensors are compared with that of pressure gradient arrays and particle velocity sensors. {copyright} {ital 1996 American Institute of Physics.}

  4. UV photolysis for accelerating pyridine biodegradation.

    PubMed

    Zhang, Yongming; Chang, Ling; Yan, Ning; Tang, Yingxia; Liu, Rui; Rittmann, Bruce E

    2014-01-01

    Pyridine, a nitrogen-containing heterocyclic compound, is slowly biodegradable, and coupling biodegradation with UV photolysis is a potential means to accelerate its biotransformation and mineralization. The initial steps of pyridine biodegradation involve mono-oxygenation reactions that have molecular oxygen and an intracellular electron carrier as cosubstrates. We employed an internal circulation baffled biofilm reactor for pyridine biodegradation following three protocols: direct biodegradation (B), biodegradation after photolysis (P+B), and biodegradation with succinic acid added (B+S). Succinic acid was the main UV-photolysis product from pyridine, and its catabolic oxidation generates internal electron carriers that may accelerate the initial steps of pyridine biodegradation. Compared with direct biodegradation of pyridine (B), the removal rate for the same concentration of photolyzed pyridine (P+B) was higher by 15 to 43%, depending on the initial pyridine concentrations (increasing through the range of 130 to 310 mg/L). Adding succinic acid alone (B+S) gave results similar to P+B, which supports that succinic acid was the main agent for accelerating the pyridine biodegradation rate. In addition, protocols P+B and B+S were similar in terms of increasing pyridine mineralization over 10 h: 84% and 87%, respectively, which were higher than with protocol B (72%). The positive impact of succinic acid-whether added directly or produced via UV photolysis-confirms that its catabolism, which produced intracellular electron carriers, accelerated the initial steps of pyridine biotransformation. PMID:24364496

  5. Cosmic Plasma Wakefield Acceleration

    NASA Astrophysics Data System (ADS)

    Chen, Pisin; Tajima, Toshiki; Takahashi, Yoshiyuki

    2002-10-01

    A cosmic acceleration mechanism is introduced which is based on the wakefields excited by the Alfven shocks in a relativistically flowing plasma. We show that there exists a threshold condition for transparency below which the accelerating particle is collision-free and suffers little energy loss in the plasma medium. The stochastic encounters of the random accelerating-decelerating phases results in a power-law energy spectrum: f([epsilon]) [is proportional to] 1/[epsilon]2. As an example, we discuss the possible production of super-GZK ultra high energy cosmic rays (UHECR) in the atmosphere of gamma ray bursts. The estimated event rate in our model agrees with that from UHECR observations. [copyright] 2002 American Institute of Physics

  6. A Prospective Cohort Study to Compare Treatment Results Between 2 Fractionation Schedules of High-Dose-Rate Intracavitary Brachytherapy (HDR-ICBT) in Patients With Cervical Cancer

    SciTech Connect

    Huang, Eng-Yen; Sun, Li-Min; Lin, Hao; Lan, Jen-Hong; Chanchien, Chan-Chao; Huang, Yu-Jie; Wang, Chang-Yu; Wang, Chong-Jong

    2013-01-01

    Purpose: To compare the treatment results of 2 fractionation schedules for high-dose-rate intracavitary brachytherapy (HDR-ICBT) in patients with cervical cancer. Methods and Materials: From June 2001 through January 2008, 267 patients with stage IB-IVA cervical cancer were enrolled in the study. All patients underwent 4-field pelvic irradiation and HDR-ICBT. The median central and parametrial doses were 39.6 Gy and 45 Gy, respectively. Patient underwent either 6 Gy Multiplication-Sign 4 (HDR-4) (n=144) or 4.5 Gy Multiplication-Sign 6 (HDR-6) (n=123) to point A of ICBT using {sup 192}Ir isotope twice weekly. The rates of overall survival, locoregional failure, distant metastasis, proctitis, cystitis, and enterocolitis were compared between HDR-4 and HDR-6. Results: There were no significant differences in the demographic data between HDR-4 and HDR-6 except for total treatment time. The 5-year proctitis rates were 23.0% and 21.5% in HDR-4 and HDR-6 (P=.399), respectively. The corresponding rates of grade 2-4 proctitis were 18.7% and 9.6% (P=.060). The corresponding rates of grades 3-4 proctitis were 5.2% and 1.3% (P=.231). Subgroup analysis revealed that HDR-4 significantly increased grade 2-4 proctitis in patients aged {>=}62 years old (P=.012) but not in patients aged <62 years (P=.976). The rates of overall survival, locoregional failure, distant metastasis, cystitis, and enterocolitis were not significantly different between HDR-4 and HDR-6 schedules. Conclusion: The small fraction size of HDR-ICBT is associated with grade 2 proctitis without compromise of prognosis in elderly patients. This schedule is suggested for patients who tolerate an additional 2 applications of HDR-ICBT.

  7. Enhancement of dissolution rate of class II drugs (Hydrochlorothiazide); a comparative study of the two novel approaches; solid dispersion and liqui-solid techniques

    PubMed Central

    Khan, Amjad; Iqbal, Zafar; Shah, Yasar; Ahmad, Lateef; Ismail; Ullah, Zia; Ullah, Aman

    2015-01-01

    Liqui-solid technique and solid dispersion formation are two novel approaches for enhancement of dissolution rate of BCS class II drugs. Liqui-solid compact converts a liquid drug or drug solution into a free flowing powder with enhanced dissolution rate. In case of solid dispersion drug is molecularly dispersed in a hydrophilic polymer in solid state. In the present study, Liqui-solid and solid dispersion techniques were applied to enhance the dissolution of the Hydrochlorothiazide. Three formulations of Hydrochlorothiazide were prepared by liqui-solid technique using micro crystalline cellulose as carrier material and colloidal silicon dioxide as coating material. Water, poly ethylene glycol-400 and Tween-60 were used as solvent system. Solid dispersions of Hydrochlorothiazide were prepared by solvent fusion method using PEG-4000 as carrier polymer. Tablets were subjected to evaluation of various physical and chemical characteristics. Dissolution profiles of tablets prepared by the novel techniques were compared with marketed conventional tablets. Model independent techniques including similarity factor, dissimilarity factor and dissolution efficiency were applied for comparison of dissolution profiles. The results obtained indicated that liqui-solid compact formulations were more effective in enhancing the dissolution rate compared with solid dispersion technique. The liqui-solid compacts improved the dissolution rate up to 95% while the solid dispersion increased it to 88%. PMID:26702260

  8. A comparative numerical study of rotating and stationary RF coils in terms of flip angle and specific absorption rate for 7 T MRI

    NASA Astrophysics Data System (ADS)

    Trakic, A.; Jin, J.; Li, M. Y.; McClymont, D.; Weber, E.; Liu, F.; Crozier, S.

    2013-11-01

    While high-field magnetic resonance imaging promises improved image quality and faster scan time, it is affected by non-uniform flip angle distributions and unsafe specific absorption rate levels within the patient, as a result of the complicated radiofrequency (RF) field - tissue interactions. This numerical study explored the possibility of using a single mechanically rotating RF coil for RF shimming and specific absorption rate management applications at 7 T. In particular, this new approach (with three different RF coil element arrangements) was compared against both an 8-channel parallel coil array and a birdcage volume coil, with and without RF current optimisation. The evaluation was conducted using an in-house developed and validated finite-difference time-domain method in conjunction with a tissue-equivalent human head model. It was found that, without current optimisation, the rotating RF coil method produced a more uniform flip angle distribution and a lower maximum global and local specific absorption rate compared to the 8-channel parallel coil array and birdcage resonator. In addition, due to the large number of degrees of freedom in the form of rotated sensitivity profiles, the rotating RF coil approach exhibited good RF shimming and specific absorption rate management performance. This suggests that the proposed method can be useful in the development of techniques that address contemporary RF issues associated with high-field magnetic resonance imaging.

  9. Enhancement of dissolution rate of class II drugs (Hydrochlorothiazide); a comparative study of the two novel approaches; solid dispersion and liqui-solid techniques.

    PubMed

    Khan, Amjad; Iqbal, Zafar; Shah, Yasar; Ahmad, Lateef; Ismail; Ullah, Zia; Ullah, Aman

    2015-11-01

    Liqui-solid technique and solid dispersion formation are two novel approaches for enhancement of dissolution rate of BCS class II drugs. Liqui-solid compact converts a liquid drug or drug solution into a free flowing powder with enhanced dissolution rate. In case of solid dispersion drug is molecularly dispersed in a hydrophilic polymer in solid state. In the present study, Liqui-solid and solid dispersion techniques were applied to enhance the dissolution of the Hydrochlorothiazide. Three formulations of Hydrochlorothiazide were prepared by liqui-solid technique using micro crystalline cellulose as carrier material and colloidal silicon dioxide as coating material. Water, poly ethylene glycol-400 and Tween-60 were used as solvent system. Solid dispersions of Hydrochlorothiazide were prepared by solvent fusion method using PEG-4000 as carrier polymer. Tablets were subjected to evaluation of various physical and chemical characteristics. Dissolution profiles of tablets prepared by the novel techniques were compared with marketed conventional tablets. Model independent techniques including similarity factor, dissimilarity factor and dissolution efficiency were applied for comparison of dissolution profiles. The results obtained indicated that liqui-solid compact formulations were more effective in enhancing the dissolution rate compared with solid dispersion technique. The liqui-solid compacts improved the dissolution rate up to 95% while the solid dispersion increased it to 88%. PMID:26702260

  10. Substituent Effects on Electrophilic Catalysis by the Carbonyl Group: Anatomy of the Rate Acceleration for PLP-Catalyzed Deprotonation of Glycine

    PubMed Central

    Crugeiras, Juan; Rios, Ana; Riveiros, Enrique; Richard, John P.

    2011-01-01

    First-order rate constants, determined by 1H NMR, are reported for deuterium exchange between solvent D2O and the α-amino carbon of glycine in the presence of increasing concentrations of carbonyl compounds (acetone, benzaldehyde and salicylaldehyde) and at different pD and buffer concentrations. These rate data were combined with 1H NMR data that define the position of the equilibrium for formation of imines/iminium ions from addition of glycine to the respective carbonyl compounds, to give second-order rate constants kDO for deprotonation of α-imino carbon by DO−. The assumption that these second-order rate constants lie on linear structure-reactivity correlations between log kOL and pKa was made in estimating the following pKas for deprotonation of α-imino carbon: pKa = 22, glycine–acetone iminium ion; pKa = 27, glycine–benzaldehyde imine; pKa ≈ 23, glycine–benzaldehyde iminium ion; and, pKa = 25, glycine–salicylaldehyde iminium ion. The much lower pKa of 17 [Toth, K.; Richard, J. P. J. Am. Chem. Soc. 2007, 129, 3013–3021] for carbon deprotonation of the adduct between 5′-deoxypyridoxal (DPL) and glycine shows that the strongly electron-withdrawing pyridinium ion is unique in driving the extended delocalization of negative charge from the α-iminium to the α-pyridinium carbon. This favors carbanion protonation at the α–pyridinium carbon, and catalysis of the 1,3-aza-allylic isomerization reaction that is a step in enzyme-catalyzed transamination reactions. An analysis of the effect of incremental changes in structure on the activity of benzaldehyde in catalysis of deprotonation of glycine shows the carbonyl group electrophile, the 2-O− ring substituent and the cation pyridinium nitrogen of DPL each make a significant contribution to the catalytic activity of this cofactor analog. The extraordinary activity of DPL in catalysis of deprotonation of α–amino carbon results from the summation of these three smaller effects. PMID:21323335

  11. Comparative assessment of erosion and deposition rates on cultivated land in the Transylvanian Plain of Romania using ¹³⁷Cs and ²¹⁰Pbex.

    PubMed

    Iurian, A R; Mabit, L; Begy, R; Cosma, C

    2013-11-01

    Soil erosion and sedimentation are natural landscape forming processes. However, they can be accelerated by human activities and therefore increase negative impacts on agricultural production as well as disturbing watershed management. Romania currently faces major environmental challenges and pressure on soil and water resources due to unsustainable farming practices and inappropriate tillage practices. The present work represents the first attempt to test the combined use of radionuclide approaches (i.e. (137)Cs and (210)Pb(ex)) to quantify soil erosion changes in cultivated Transylvanian fields (Romania) at different temporal scales. Fourteen soil cores were collected along two transects in a cultivated field and two reference sites were selected to establish the mean reference inventories for both (137)Cs and (210)Pb(ex). A value of 5460 ± 880 Bq m(-2) (n = 10; CV = 16%) was determined for the (137)Cs mean reference inventory for both sites, given as areal activity ± standard deviation, at 2σ confidence interval. As regarding (210)Pb(ex) reference inventory, its value (9640 Bq m(-2)) is only given by the areal activity of one soil core from the second site. The high erosion rates obtained with the (210)Pb(ex) approach are an effect of the up and down ploughing practices which took place at the time of the local agricultural cooperative starting in the late 1950s. The middle-term redistribution rates provided by the (137)Cs technique highlighted preponderant deposition processes in the field investigated, reflecting the changes in the cultivation system with ploughing across the slope at the beginning of 1990s. PMID:23522558

  12. The rates of change of the stochastic trajectories of acceleration variability are a good predictor of normal aging and of the stage of Parkinson's disease

    PubMed Central

    Torres, Elizabeth B.

    2013-01-01

    The accelerometer data from mobile smart phones provide stochastic trajectories that change over time. This rate of change is unique to each person and can be well-characterized by the continuous two-parameter family of Gamma probability distributions. Accordingly, on the Gamma plane each participant can be uniquely localized by the shape and the scale parameters of the Gamma probability distribution. The scatter of such points contains information that can unambiguously separate the normal controls (NC) from those patients with Parkinson's disease (PD) that are at a later stage of the disease. In general normal aging seems conducive of more predictable patterns of variation in the accelerometer data. Yet this trend breaks down in PD where the statistical signatures seem to be a more relevant predictor of the stage of the disease. Those patients at a later stage of the disease have more random and noisier patterns than those in the earlier stages, whose statistics resemble those of the older NC. Overall the peak rates of change of the stochastic trajectories of the accelerometer are a good predictor of the stage of PD and of the age of a “normally” aging individual. PMID:23882193

  13. Dielectric laser accelerators

    NASA Astrophysics Data System (ADS)

    England, R. Joel; Noble, Robert J.; Bane, Karl; Dowell, David H.; Ng, Cho-Kuen; Spencer, James E.; Tantawi, Sami; Wu, Ziran; Byer, Robert L.; Peralta, Edgar; Soong, Ken; Chang, Chia-Ming; Montazeri, Behnam; Wolf, Stephen J.; Cowan, Benjamin; Dawson, Jay; Gai, Wei; Hommelhoff, Peter; Huang, Yen-Chieh; Jing, Chunguang; McGuinness, Christopher; Palmer, Robert B.; Naranjo, Brian; Rosenzweig, James; Travish, Gil; Mizrahi, Amit; Schachter, Levi; Sears, Christopher; Werner, Gregory R.; Yoder, Rodney B.

    2014-10-01

    The use of infrared lasers to power optical-scale lithographically fabricated particle accelerators is a developing area of research that has garnered increasing interest in recent years. The physics and technology of this approach is reviewed, which is referred to as dielectric laser acceleration (DLA). In the DLA scheme operating at typical laser pulse lengths of 0.1 to 1 ps, the laser damage fluences for robust dielectric materials correspond to peak surface electric fields in the GV /m regime. The corresponding accelerating field enhancement represents a potential reduction in active length of the accelerator between 1 and 2 orders of magnitude. Power sources for DLA-based accelerators (lasers) are less costly than microwave sources (klystrons) for equivalent average power levels due to wider availability and private sector investment. Because of the high laser-to-particle coupling efficiency, required pulse energies are consistent with tabletop microJoule class lasers. Combined with the very high (MHz) repetition rates these lasers can provide, the DLA approach appears promising for a variety of applications, including future high-energy physics colliders, compact light sources, and portable medical scanners and radiative therapy machines.

  14. Comparative analysis of hatching rates and clutch sizes of Nile crocodile (Crocodylus niloticus) eggs collected on- and off-farm in Zimbabwe.

    PubMed

    Khosa, Patricia; Imbayarwo-Chikosi, Venancio Edward; Hamandishe, Vimbai

    2012-04-01

    The Nile crocodile (Crocodylus niloticus) is a large aquatic reptile predominant in the tropics in Africa and Zimbabwe in particular. Clutch sizes and hatching rates of Nile crocodile eggs collected from the wild and on-farm in Lowveld, Highveld and Kariba regions of Zimbabwe were evaluated. A total of 274 egg records for the period 2000 to 2008 from 39 farms were collected from the Crocodile Farmers Association of Zimbabwe. The effect of source of eggs was analysed using the non-parametric one way analysis of variance procedure of SAS Version 9.1.3. Wilcoxon signed rank test for independent samples was used to compare the mean hatching rates and clutch sizes for eggs collected from the different sources by region. The degree of association between clutch sizes and the hatching rates by source and region was determined using the Spearman's rank correlation test. Source of eggs had no effect (P > 0.05) on hatching rates in all the regions but significantly influenced (P < 0.05) clutch sizes in Lowveld and Kariba. In these regions, clutch sizes in the wild were significantly (P < 0.05) higher than those on-farm. Correlation estimates between clutch size and hatching rates were weak and non-significant (P > 0.05) for the different sources of eggs in all regions. Full utilization of the wild resource would reduce challenges relating to shortage of captive breeders and high cost of rearing breeders and hence increase productivity. PMID:21947863

  15. Incidence Rate and Epidemiological and Clinical Aspects of Kawasaki Disease in Children of Maghrebi Origin in the Province of Quebec, Canada, Compared to the Country of Origin

    PubMed Central

    Gorrab, Arbia Abir; Fournier, Anne; Bouaziz, Asma Abed; Spigelblatt, Linda; Scuccimarri, Rosie; Mrabet, Ali; Dahdah, Nagib

    2016-01-01

    The incidence of Kawasaki disease in Maghreb countries is apparently low, unlike those living in the province of Quebec, Canada. This retrospective study compared Maghrebi children living in Quebec to the countries of origin, Morocco, Algeria, and Tunisia. The annualized incidence rate in Quebec (18.49/year/100 000 children under 5 years of age) was 4 to 12 times higher than in Tunisia, Morocco, and Algeria (0.95, 4.52, and 3.15, respectively). The prevalence of incomplete diagnostic criteria was higher in Quebec at 39%, Morocco 43%, and Tunisia 39% compared to Algeria at 8%, with minimal delayed diagnosis (7%) only in Quebec compared to 30%, 35%, and 62%, respectively (P < .001). The rate of coronary aneurysms was comparable however (11% in Quebec vs 4%, 10%, and 25%, in Tunisia, Morocco, and Algeria, respectively; P = .31). The higher incidence of Kawasaki disease in the Maghreb community in Quebec versus the countries of origin seems due to underdiagnosis, which represents a public health concern in those countries. PMID:27336001

  16. Incidence Rate and Epidemiological and Clinical Aspects of Kawasaki Disease in Children of Maghrebi Origin in the Province of Quebec, Canada, Compared to the Country of Origin.

    PubMed

    Gorrab, Arbia Abir; Fournier, Anne; Bouaziz, Asma Abed; Spigelblatt, Linda; Scuccimarri, Rosie; Mrabet, Ali; Dahdah, Nagib

    2016-01-01

    The incidence of Kawasaki disease in Maghreb countries is apparently low, unlike those living in the province of Quebec, Canada. This retrospective study compared Maghrebi children living in Quebec to the countries of origin, Morocco, Algeria, and Tunisia. The annualized incidence rate in Quebec (18.49/year/100 000 children under 5 years of age) was 4 to 12 times higher than in Tunisia, Morocco, and Algeria (0.95, 4.52, and 3.15, respectively). The prevalence of incomplete diagnostic criteria was higher in Quebec at 39%, Morocco 43%, and Tunisia 39% compared to Algeria at 8%, with minimal delayed diagnosis (7%) only in Quebec compared to 30%, 35%, and 62%, respectively (P < .001). The rate of coronary aneurysms was comparable however (11% in Quebec vs 4%, 10%, and 25%, in Tunisia, Morocco, and Algeria, respectively; P = .31). The higher incidence of Kawasaki disease in the Maghreb community in Quebec versus the countries of origin seems due to underdiagnosis, which represents a public health concern in those countries. PMID:27336001

  17. Stochastic modeling of Lagrangian accelerations

    NASA Astrophysics Data System (ADS)

    Reynolds, Andy

    2002-11-01

    It is shown how Sawford's second-order Lagrangian stochastic model (Phys. Fluids A 3, 1577-1586, 1991) for fluid-particle accelerations can be combined with a model for the evolution of the dissipation rate (Pope and Chen, Phys. Fluids A 2, 1437-1449, 1990) to produce a Lagrangian stochastic model that is consistent with both the measured distribution of Lagrangian accelerations (La Porta et al., Nature 409, 1017-1019, 2001) and Kolmogorov's similarity theory. The later condition is found not to be satisfied when a constant dissipation rate is employed and consistency with prescribed acceleration statistics is enforced through fulfilment of a well-mixed condition.

  18. Compact accelerator

    DOEpatents

    Caporaso, George J.; Sampayan, Stephen E.; Kirbie, Hugh C.

    2007-02-06

    A compact linear accelerator having at least one strip-shaped Blumlein module which guides a propagating wavefront between first and second ends and controls the output pulse at the second end. Each Blumlein module has first, second, and third planar conductor strips, with a first dielectric strip between the first and second conductor strips, and a second dielectric strip between the second and third conductor strips. Additionally, the compact linear accelerator includes a high voltage power supply connected to charge the second conductor strip to a high potential, and a switch for switching the high potential in the second conductor strip to at least one of the first and third conductor strips so as to initiate a propagating reverse polarity wavefront(s) in the corresponding dielectric strip(s).

  19. Comparative study of Gamow-Teller strength distributions in the odd-odd nucleus {sup 50}V and its impact on electron capture rates in astrophysical environments

    SciTech Connect

    Nabi, Jameel-Un; Sajjad, Muhammad

    2007-11-15

    Gamow-Teller (GT) strength transitions are an ideal probe for testing nuclear structure models. In addition to nuclear structure, GT transitions in nuclei directly affect the early phases of Type Ia and Type-II supernovae core collapse since the electron capture rates are partly determined by these GT transitions. In astrophysics, GT transitions provide an important input for model calculations and element formation during the explosive phase of a massive star at the end of its life-time. Recent nucleosynthesis calculations show that odd-odd and odd-A nuclei cause the largest contribution in the rate of change of lepton-to-baryon ratio. In the present manuscript, we have calculated the GT strength distributions and electron capture rates for odd-odd nucleus {sup 50}V by using the pn-QRPA theory. At present {sup 50}V is the first experimentally available odd-odd nucleus in fp-shell nuclei. We also compare our GT strength distribution with the recently measured results of a {sup 50}V(d, {sup 2}He){sup 50}Ti experiment, with the earlier work of Fuller, Fowler, and Newman (referred to as FFN) and subsequently with the large-scale shell model calculations. One curious finding of the paper is that the Brink's hypothesis, usually employed in large-scale shell model calculations, is not a good approximation to use at least in the case of {sup 50}V. SNe Ia model calculations performed using FFN rates result in overproduction of {sup 50}Ti, and were brought to a much acceptable value by employing shell model results. It might be interesting to study how the composition of the ejecta using presently reported QRPA rates compare with the observed abundances.

  20. BICEP's acceleration

    SciTech Connect

    Contaldi, Carlo R.

    2014-10-01

    The recent Bicep2 [1] detection of, what is claimed to be primordial B-modes, opens up the possibility of constraining not only the energy scale of inflation but also the detailed acceleration history that occurred during inflation. In turn this can be used to determine the shape of the inflaton potential V(φ) for the first time — if a single, scalar inflaton is assumed to be driving the acceleration. We carry out a Monte Carlo exploration of inflationary trajectories given the current data. Using this method we obtain a posterior distribution of possible acceleration profiles ε(N) as a function of e-fold N and derived posterior distributions of the primordial power spectrum P(k) and potential V(φ). We find that the Bicep2 result, in combination with Planck measurements of total intensity Cosmic Microwave Background (CMB) anisotropies, induces a significant feature in the scalar primordial spectrum at scales k∼ 10{sup -3} Mpc {sup -1}. This is in agreement with a previous detection of a suppression in the scalar power [2].

  1. Exploiting comparative mapping among Brassica species to accelerate the physical delimitation of a genic male-sterile locus (BnRf) in Brassica napus.

    PubMed

    Xie, Yanzhou; Dong, Faming; Hong, Dengfeng; Wan, Lili; Liu, Pingwu; Yang, Guangsheng

    2012-07-01

    The recessive genic male sterility (RGMS) line 9012AB has been used as an important pollination control system for rapeseed hybrid production in China. Here, we report our study on physical mapping of one male-sterile locus (BnRf) in 9012AB by exploiting the comparative genomics among Brassica species. The genetic maps around BnRf from previous reports were integrated and enriched with markers from the Brassica A7 chromosome. Subsequent collinearity analysis of these markers contributed to the identification of a novel ancestral karyotype block F that possibly encompasses BnRf. Fourteen insertion/deletion markers were further developed from this conserved block and genotyped in three large backcross populations, leading to the construction of high-resolution local genetic maps where the BnRf locus was restricted to a less than 0.1-cM region. Moreover, it was observed that the target region in Brassica napus shares a high collinearity relationship with a region from the Brassica rapa A7 chromosome. A BnRf-cosegregated marker (AT3G23870) was then used to screen a B. napus bacterial artificial chromosome (BAC) library. From the resulting 16 positive BAC clones, one (JBnB089D05) was identified to most possibly contain the BnRf (c) allele. With the assistance of the genome sequence from the Brassica rapa homolog, the 13.8-kb DNA fragment covering both closest flanking markers from the BAC clone was isolated. Gene annotation based on the comparison of microcollinear regions among Brassica napus, B. rapa and Arabidopsis showed that five potential open reading frames reside in this fragment. These results provide a foundation for the characterization of the BnRf locus and allow a better understanding of the chromosome evolution around BnRf. PMID:22382487

  2. Accelerator simulation of astrophysical processes

    NASA Technical Reports Server (NTRS)

    Tombrello, T. A.

    1983-01-01

    Phenomena that involve accelerated ions in stellar processes that can be simulated with laboratory accelerators are described. Stellar evolutionary phases, such as the CNO cycle, have been partially explored with accelerators, up to the consumption of He by alpha particle radiative capture reactions. Further experimentation is indicated on reactions featuring N-13(p,gamma)O-14, O-15(alpha, gamma)Ne-19, and O-14(alpha,p)F-17. Accelerated beams interacting with thin foils produce reaction products that permit a determination of possible elemental abundances in stellar objects. Additionally, isotopic ratios observed in chondrites can be duplicated with accelerator beam interactions and thus constraints can be set on the conditions producing the meteorites. Data from isotopic fractionation from sputtering, i.e., blasting surface atoms from a material using a low energy ion beam, leads to possible models for processes occurring in supernova explosions. Finally, molecules can be synthesized with accelerators and compared with spectroscopic observations of stellar winds.

  3. Comparison of outcomes in a traditional versus accelerated nursing curriculum.

    PubMed

    Aktan, Nadine M; Bareford, Connie G; Bliss, Julie B; Connolly, Kathleen; DeYoung, Sandra; Lancellotti Sullivan, Katherine; Tracy, Janet

    2009-01-01

    In this descriptive study, graduates of a traditional baccalaureate nursing program were compared with graduates of an accelerated baccalaureate program at the same university between 1991 and 2006. A survey was sent to a random sample of two groups: traditional baccalaureate graduates and graduates of the accelerated program who had previous degrees in another major and completed the nursing curriculum in a shorter time frame than the traditional students, resulting in a total sample of 73 graduates. Outcome variables included demographics, NCLEX passing rates, transitioning to the professional role, employment, professional development, certifications and self-reported reasons the respondents entered the nursing profession and why they remained. There were no statistically significant differences between the two groups on these variables. Results of a t-test revealed that the GPA of the accelerated group was significantly higher than the traditional group. Future considerations include the impact that accelerated program development may have on both the current and projected nursing shortage. PMID:19409069

  4. Rationale and Enrollment Results for a Partially Randomized Patient Preference Trial to Compare Continuation Rates of Short-Acting and Long-Acting Reversible Contraception

    PubMed Central

    Hubacher, David; Spector, Hannah; Monteith, Charles; Chen, Pai-Lien; Hart, Catherine

    2014-01-01

    Objectives Most published contraceptive continuation rates have scientific limitations and cannot be compared; this is particularly true for dissimilar contraceptives. This study uses a new approach to determine if high continuation rates of long-acting reversible contraception (LARC) and protection from unintended pregnancy are observable in a population not self-selecting to use LARC. Study Design We are conducting a partially randomized patient preference trial to compare continuation rates of short-acting reversible contraception (SARC) and LARC. Only women seeking SARC were invited to participate. Participants chose to be in the preference cohort (self-selected method use) or opted to be randomized to SARC or LARC; only those in the randomized cohort received free product. We compared participant characteristics, reasons for not trying LARC previously, and the contraceptive choices that were made. Results We enrolled 917 eligible women; 57% chose to be in the preference cohort and 43% opted for the randomized trial. The preference and randomized cohorts were similar on most factors. However, the randomized cohort was more likely than the preference cohort to be uninsured (48% versus 36%, respectively) and to cite cost as a reason for not trying LARC previously (50% versus 10%) (p<0.01 for both comparisons). In the preference cohort, fear of pain/injury/side effects/health risks were the predominant reasons (cited by over 25%) for not trying LARC previously (p<0.01 in comparison to randomized cohort). Conclusions Enrollment was successful and the process created different cohorts to compare contraceptive continuation rates and unintended pregnancy in this ongoing trial. The choices participants made were associated with numerous factors; lack of insurance was associated with participation in the randomized trial. Implications This partially randomized patient preference trial will provide new estimates of contraceptive continuation rates, such that any benefits

  5. Effects of sex-sorting and sperm dosage on conception rates of Holstein heifers: is comparable fertility of sex-sorted and conventional semen plausible?

    PubMed

    Dejarnette, J M; Leach, M A; Nebel, R L; Marshall, C E; McCleary, C R; Moreno, J F

    2011-07-01

    The conception rates of Holstein heifers after AI with 2.1 or 10 × 10(6) sperm dosages of sex-sorted or conventionally processed sperm were compared. Ejaculates collected by artificial vagina from 8 Holstein sires were cryopreserved at either 2.1 or 10 × 10(6) sperm per dose with or without sorting to 90% purity for X-chromosome-bearing spermatozoa using flow cytometry. All treatments were processed in an egg-yolk (20%), TRIS, glycerol (7%) extender and packaged in color-coded 0.25-mL French straws. Straws (n=350 straws/treatment per sire) were packaged and distributed in aliquots of 12 (3 straws of each treatment) to 51 herds of Holstein heifers. Straw color was recorded in the on-farm record keeping system at the time of AI and retrieved by electronic download. In total, 9,172 services were recovered, providing a mean sample size of 287±3.5 services/sperm dose per semen type within sire (range: 248 to 318). Conception rates were influenced by the main effects of herd, sire, semen type, sperm dosage, and service number. The herd by sperm dosage interaction was the only interaction determined to be significant and implies that some herds (technicians) are more proficient than others at maintaining high levels of conception with decreased sperm dosages. Across herds and sires, the conception rates of each semen type by sperm dosage combination were as follows: 2.1 × 10(6) sex-sorted, 38%, n=2,319; 10 × 10(6) sex-sorted, 44%, n=2,279; 2.1 × 10(6) conventional, 55%, n=2,282; and 10 × 10(6) conventional, 60%, n=2,292. The observation that conception rates of sex-sorted semen were improved by the 10 × 10(6) sperm dosage is encouraging toward the prospectus of development of a commercially available sex-sorted product with improved conception potential over existing technology. However, the failure of the 10 × 10(6) sex-sorted sperm dosage to achieve conception rates comparable to either dosage of conventional semen is somewhat discouraging toward the

  6. Critical mechanical structure of superconducting high current coils for fast ramped accelerator magnets with high repetition rates in long term operation

    NASA Astrophysics Data System (ADS)

    Fischer, E.; Schnizer, P.; Weiss, K.; Nyilas, A.; Mierau, A.; Sikler, G.

    2010-06-01

    The heavy ion synchrotron SIS100 is the core component of the Facility for Antiproton and Ion Research (FAIR) currently under construction at GSI in Darmstadt. It is rapidly cycled with a ramp rate of 4 T/s up to 2 T maximum field and a repetition frequency of 1 Hz. The superconducting coils of the Nuclotron-type magnets utilise a hollow cable cooled with a forced two phase helium flow. These coils must operate reliably over a period of at least 20 years and thus survive 2 · 10 load cycles. Intensive R&D is necessary to find the optimal solution preventing any possible damage of the coils by the fast pulsing loads over the life time taking into account the complex fine structure of the cable and coil designs as well as its sensitive influence on the field quality, AC loss generation and quench protection. We used FEM codes to analyse critical aspects of various design options and had manufactured coils for detailed mechanical tests. These tests on samples extracted from the coil are: thermal expansion measurements in all three directions on the cable package itself and its composite elements, compression tests and investigation of the Inter Laminar Shear Stress (ILSS). The stress strain behaviour of the cable package was measured along the transversal direction; the most important one to sustain the cycling load by Lorentz forces. A second sample was fatigue tested. Successful integral operation test results for the coil mechanics have been obtained within our first experimental runs on the prototype dipole magnets already started at GSI in the end of 2008.

  7. Advanced concepts for acceleration

    SciTech Connect

    Keefe, D.

    1986-07-01

    Selected examples of advanced accelerator concepts are reviewed. Such plasma accelerators as plasma beat wave accelerator, plasma wake field accelerator, and plasma grating accelerator are discussed particularly as examples of concepts for accelerating relativistic electrons or positrons. Also covered are the pulsed electron-beam, pulsed laser accelerator, inverse Cherenkov accelerator, inverse free-electron laser, switched radial-line accelerators, and two-beam accelerator. Advanced concepts for ion acceleration discussed include the electron ring accelerator, excitation of waves on intense electron beams, and two-wave combinations. (LEW)

  8. Comparing historical catch rates of American shad in multifilament and monofilament nets: A step toward setting restoration targets for Virginia stocks

    USGS Publications Warehouse

    Maki, K.L.; Hoenig, J.M.; Olney, J.E.; Heisey, D.M.

    2006-01-01

    Recreational and commercial harvest of American shad Alosa sapidissima in the Virginia waters of the Chesapeake Bay and its tributaries has been prohibited since 1994. The Atlantic States Marine Fisheries Commission Shad and River Herring Management Plan requires that Virginia develop restoration targets for its shad populations, but estimates of their sizes are not available and there is little information about historic population levels. Thus, establishing restoration targets based on population size is problematic. A current spawning stock monitoring program yields catch rate information that can be compared with historic catch rate information recorded in commercial fishery logbooks from the 1950s and the 1980s. However, multifilament gill nets were used in the 1950s and monofilament nets were used in the 1980s (as well as in the current monitoring program). A Latin square design was employed to test the differences in relative fishing power of the two gear types over 2 years of seasonal sampling on the York River, Virginia. Estimates are that the monofilament nets are roughly twice as efficient as the multifilament nets. Reported catch rates in the 1950s and 1980s are roughly equivalent. However, when adjustments are made for the differences in fishing gear, catch rates for the 1950s are twice as high as those during the 1980s. These results provide valuable information for setting restoration targets for Virginia stocks of American shad. ?? Copyright by the American Fisheries Society 2006.

  9. Assessment of ambient gamma dose rate around a prospective uranium mining area of South India - A comparative study of dose by direct methods and soil radioactivity measurements

    NASA Astrophysics Data System (ADS)

    Karunakara, N.; Yashodhara, I.; Sudeep Kumara, K.; Tripathi, R. M.; Menon, S. N.; Kadam, S.; Chougaonkar, M. P.

    Indoor and outdoor gamma dose rates were evaluated around a prospective uranium mining region - Gogi, South India through (i) direct measurements using a GM based gamma dose survey meter, (ii) integrated measurement days using CaSO4:Dy based thermo luminescent dosimeters (TLDs), and (iii) analyses of 273 soil samples for 226Ra, 232Th, and 40K activity concentration using HPGe gamma spectrometry. The geometric mean values of indoor and outdoor gamma dose rates were 104 nGy h-1 and 97 nGy h-1, respectively with an indoor to outdoor dose ratio of 1.09. The gamma dose rates and activity concentrations of 226Ra, 232Th, and 40K varied significantly within a small area due to the highly localized mineralization of the elements. Correlation study showed that the dose estimated from the soil radioactivity is better correlated with that measured directly using the portable survey meter, when compared to that obtained from TLDs. This study showed that in a region having localized mineralization in situ measurements using dose survey meter provide better representative values of gamma dose rates.

  10. Rate of permeabilization of giant vesicles by amphiphilic polyacrylates compared to the adsorption of these polymers onto large vesicles and tethered lipid bilayers.

    PubMed

    Vial, F; Cousin, F; Bouteiller, L; Tribet, C

    2009-07-01

    We examined by fluorescence microscopy the permeabilization of giant vesicles by hydrophobically modified polyacrylates (called amphipols). Amphipols trigger permeabilization to FITC-dextran of egg-PC/DPPA vesicles with no breakage of the lipid bilayers. The polyanionic amphipols were passing through bilayers as shown by permeabilization of multilamellar vesicles. Remarkably, the vesicles were not simultaneously permeable but became leaky one after the other. Altogether, our observations suggest a random formation of pores having diameters above a few nanometers. Decreasing pH and increasing ionic strength and polymer concentration were increasing the rate of permeabilization. The rate and efficiency of permeabilization was compared to the rate and density of adsorption of amphipols onto lipid membranes (as estimated by titration calorimetry onto large unilamellar vesicles and neutron reflectivity measurements on tethered bilayers). The polymer adsorption layer is built up in a few minutes. We conclude that the rate-limiting step for permeabilization is not the adsorption from the bulk solution but relates to slow intramembrane reorganizations. PMID:19371041

  11. Assessment of Salivary Flow Rate and pH Among Areca Nut Chewers and Oral Submucous Fibrosis Subjects: A Comparative Study

    PubMed Central

    Abdul Khader, Nishat Fatima; Dyasanoor, Sujatha

    2015-01-01

    Background: To assess and compare the salivary flow rate (SFR) and salivary pH among areca nut chewers, oral submucous fibrosis (OSMF) patients and apparently healthy individuals. Methods: A comparative study was conducted to assess and compare the SFR and pH among 135 outpatients (45 areca nut chewers + 45 OSMF + 45 control) at The Oxford Dental College and Research Hospital, Bangalore, India. Subjects were interviewed using structural proforma and Modified Schirmer strips and pH paper were implemented for assessing SFR and pH respectively. Statistical analysis was done using IBM SPSS ver. 21.0 software. Results: A statistically significant increase in SFR (35.7 mm at 3rd minutes) among areca nut group and a decrease in SFR among OSMF group (23.4 mm at 3rd minutes) when compared to apparently healthy subjects (30.7 mm at 3rd minutes). The mean pH among areca nut, OSMF and control groups was 6.76, 6.82, and 6.74 respectively with no statistical significance. Conclusions: The observation and findings of the study clearly showed hypersalivation among areca nut group and hyposalivation among OSMF group, with no significant change in salivary pH when compared to healthy subjects. PMID:26473160

  12. Carica papaya Leaves Juice Significantly Accelerates the Rate of Increase in Platelet Count among Patients with Dengue Fever and Dengue Haemorrhagic Fever.

    PubMed

    Subenthiran, Soobitha; Choon, Tan Chwee; Cheong, Kee Chee; Thayan, Ravindran; Teck, Mok Boon; Muniandy, Prem Kumar; Afzan, Adlin; Abdullah, Noor Rain; Ismail, Zakiah

    2013-01-01

    The study was conducted to investigate the platelet increasing property of Carica papaya leaves juice (CPLJ) in patients with dengue fever (DF). An open labeled randomized controlled trial was carried out on 228 patients with DF and dengue haemorrhagic fever (DHF). Approximately half the patients received the juice, for 3 consecutive days while the others remained as controls and received the standard management. Their full blood count was monitored 8 hours for 48 hours. Gene expression studies were conducted on the ALOX 12 and PTAFR genes. The mean increase in platelet counts were compared in both groups using repeated measure ANCOVA. There was a significant increase in mean platelet count observed in the intervention group (P < 0.001) but not in the control group 40 hours since the first dose of CPLJ. Comparison of mean platelet count between intervention and control group showed that mean platelet count in intervention group was significantly higher than control group after 40 and 48 hours of admission (P < 0.01). The ALOX 12 (FC  =  15.00) and PTAFR (FC  =  13.42) genes were highly expressed among those on the juice. It was concluded that CPLJ does significantly increase the platelet count in patients with DF and DHF. PMID:23662145

  13. Accelerators and the Accelerator Community

    SciTech Connect

    Malamud, Ernest; Sessler, Andrew

    2008-06-01

    In this paper, standing back--looking from afar--and adopting a historical perspective, the field of accelerator science is examined. How it grew, what are the forces that made it what it is, where it is now, and what it is likely to be in the future are the subjects explored. Clearly, a great deal of personal opinion is invoked in this process.

  14. Modulational effects in accelerators

    SciTech Connect

    Satogata, T.

    1997-12-01

    We discuss effects of field modulations in accelerators, specifically those that can be used for operational beam diagnostics and beam halo control. In transverse beam dynamics, combined effects of nonlinear resonances and tune modulations influence diffusion rates with applied tune modulation has been demonstrated. In the longitudinal domain, applied RF phase and voltage modulations provide mechanisms for parasitic halo transport, useful in slow crystal extraction. Experimental experiences with transverse tune and RF modulations are also discussed.

  15. Linear induction accelerator

    DOEpatents

    Buttram, M.T.; Ginn, J.W.

    1988-06-21

    A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities. 4 figs.

  16. Comparing past accumulation rate reconstructions in East Antarctic ice cores using 10Be, water isotopes and CMIP5-PMIP3 models

    NASA Astrophysics Data System (ADS)

    Cauquoin, A.; Landais, A.; Raisbeck, G. M.; Jouzel, J.; Bazin, L.; Kageyama, M.; Peterschmitt, J.-Y.; Werner, M.; Bard, E.; Aster Team

    2015-03-01

    Ice cores are exceptional archives which allow us to reconstruct a wealth of climatic parameters as well as past atmospheric composition over the last 800 kyr in Antarctica. Inferring the variations in past accumulation rate in polar regions is essential both for documenting past climate and for ice core chronology. On the East Antarctic Plateau, the accumulation rate is so small that annual layers cannot be identified and accumulation rate is mainly deduced from the water isotopic composition assuming constant temporal relationships between temperature, water isotopic composition and accumulation rate. Such an assumption leads to large uncertainties on the reconstructed past accumulation rate. Here, we use high-resolution beryllium-10 (10Be) as an alternative tool for inferring past accumulation rate for the EPICA Dome C ice core, in East Antarctica. We present a high-resolution 10Be record covering a full climatic cycle over the period 269 to 355 ka from Marine Isotope Stage (MIS) 9 to 10, including a period warmer than pre-industrial (MIS 9.3 optimum). After correcting 10Be for the estimated effect of the palaeomagnetic field, we deduce that the 10Be reconstruction is in reasonably good agreement with EDC3 values for the full cycle except for the period warmer than present. For the latter, the accumulation is up to 13% larger (4.46 cm ie yr-1 instead of 3.95). This result is in agreement with the studies suggesting an underestimation of the deuterium-based accumulation for the optimum of the Holocene (Parrenin et al. 2007a). Using the relationship between accumulation rate and surface temperature from the saturation vapour relationship, the 10Be-based accumulation rate reconstruction suggests that the temperature increase between the MIS 9.3 optimum and present day may be 2.4 K warmer than estimated by the water isotopes reconstruction. We compare these reconstructions to the available model results from CMIP5-PMIP3 for a glacial and an interglacial state, i

  17. Localized Ionospheric Particle Acceleration and Wave Acceleration of Auroral Ions: Amicist Data Set

    NASA Technical Reports Server (NTRS)

    Lynch, Kristina A.

    1999-01-01

    Research supported by this grant covered two main topics: auroral ion acceleration from ELF-band wave activity, and from VLF-spikelet (lower hybrid solitary structure) wave activity. Recent auroral sounding rocket data illustrate the relative significance of various mechanisms for initiating auroral ion outflow. Two nightside mechanisms are shown in detail. The first mechanism is ion acceleration within lower hybrid solitary wave events. The new data from this two payload mission show clearly that: (1) these individual events are spatially localized to scales approximately 100 m wide perpendicular to B, in agreement with previous investigations of these structures, and (2) that the probability of occurrence of the events is greatest at times of maximum VLF wave intensity. The second mechanism is ion acceleration by broadband, low frequency electrostatic waves, observed in a 30 km wide region at the poleward edge of the arc. The ion fluxes from the two mechanisms are compared and it is shown that while lower hybrid solitary structures do indeed accelerate ions in regions of intense VLF waves, the outflow from the electrostatic ion wave acceleration region is dominant for the aurora investigated by this sounding rocket, AMICIST. The fluxes are shown to be consistent with DE-1 and Freja outflow measurements, indicating that the AMICIST observations show the low altitude, microphysical signatures of nightside auroral outflow. In this paper, we present a review of sounding rocket observations of the ion acceleration seen nightside auroral zone lower hybrid solitary structures. Observations from Topaz3, Amicist, and Phaze2 are presented on various spatial scales, including the two-point measurements of the Amicist mission. From this collection of observations, we will demonstrate the following characteristics of transverse ion acceleration (TAI) in LHSS. The ion acceleration process is narrowly confined to 90 degrees pitch angle, in spatially confined regions of up to a

  18. Comparative Survival [Rate] Study (CSS) of Hatchery PIT-tagged Chinook; Migration Years 1996-1998 Mark/Recapture Activities, 2000 Annual Report.

    SciTech Connect

    Berggren, Thomas J.; Basham, Larry R.

    2000-10-01

    The Comparative Survival Rate Study (CSS) is a multi-year program of the fishery agencies and tribes to measure the smolt-to-adult survival rates of hatchery spring and summer chinook at major production hatcheries in the Snake River basin and at selected hatcheries in the lower Columbia River. The CSS also compares the smolt-to-adult survival rates for Snake River basin chinook that were transported versus those that migrated in-river to below Bonneville Dam. Estimates of smolt-to-adult survival rates will be made both from Lower Granite Dam back to Lower Granite Dam (upriver stocks) and from the hatchery back to the hatchery (upriver and downriver stocks). This status report covers the first three migration years, 1996 to 1998, of the study. Study fish were implanted with a PIT (Passive Integrated Transponder) tag which allows unique identification of individual fish. Beginning in 1997, a predetermined proportion of the PIT tagged study fish in the collection/bypass channel at the transportation sites, such as Lower Granite and Little Goose dams, was purposely routed to the raceways for transportation and the rest was routed back to the river. Two categories of in-river migrating fish are used in this study. The in-river group most representative of the non-tagged fish are fish that migrate past Lower Granite, Little Goose, and Lower Monumental dams undetected in the bypass systems. This is because all non-tagged fish collected at these three dams are currently being transported. The other in-river group contains those fish remaining in-river below Lower Monumental Dam that had previously been detected at one or more dams. The number of fish starting at Lower Granite dam that are destined to one of these two in-river groups must be estimated. The Jolly-Seber capture-recapture methodology was used for that purpose. Adult (including jacks) study fish returning to the hatcheries in the Snake River basin were sampled at the Lower Granite Dam adult trap. There the PIT

  19. Comparative Survival Rate Study (CSS) of Hatchery PIT-tagged Chinook; Oregon Department of Fish and Wildlife, Annual Report 2002-2003.

    SciTech Connect

    Jonasson, Brian

    2004-02-01

    We PIT-tagged juvenile spring chinook salmon reared at Lookingglass Hatchery in October 2002 as part of the Comparative Survival Rate Study (CSS) for migratory year (MY) 2003. We tagged 20,950 Imnaha stock spring chinook salmon, and after mortality and tag loss, we allowed the remaining 20,904 fish to leave the acclimation pond at our Imnaha River satellite facility beginning 1 April 2003 to begin their seaward migration. The fish remaining in the pond were forced out on 15 April 2003. We tagged 20,820 Catherine Creek stock captive and conventional brood progeny spring chinook salmon, and after mortality and tag loss, we allowed the remaining 20,628 fish to leave the acclimation ponds at our Catherine Creek satellite facility beginning during two acclimation periods. The volitional release for the early acclimation group began 12 March 2003, and all remaining fish were forced out of the ponds on 23 March 2003. The volitional release for the late acclimation group began 31 March 2003, and all remaining fish were forced out of the ponds on 14 April 2003. We estimated survival rates, from release to Lower Granite Dam in MY 2003, for three stocks of hatchery spring chinook salmon tagged at Lookingglass Hatchery to determine their relative migration performance. Survival rates for the Imnaha River, Lostine River, and Catherine Creek stocks were 0.714, 0.557, and 0.350, respectively. We PIT-tagged 20,944 BY 2002 Imnaha River stock and 20,980 BY 2002 Catherine Creek stock captive and conventional brood progeny in October and November 2003 as part of the CSS for MY 2004. From tagging to January 28, 2004, the rates of mortality and tag loss for Imnaha River stock were 0.16% and 0.04%, respectively. Catherine Creek stock, during the same period, had rates of mortality and tag loss of 0.19% and 0.06%, respectively.

  20. Accelerated Aging of Lead-Free Propellant

    NASA Technical Reports Server (NTRS)

    Furrow, Keith W.; Jervey, David D.

    2000-01-01

    Following higher than expected 2-NDPA depletion rates in a lead-free doublebase formulation (RPD-422), an accelerated aging study was conducted to verify the depletion rates. A test plan was prepared to compare the aging characteristics of lead-free propellant and NOSIH-AA2. The study was also designed to determine which lead-free ballistic modifiers accelerated 2-NDPA depletion. The increased depletion rate occurred in propellants containing monobasic copper salicylate. Four lead-free propellants were then formulated to improved aging characteristics over previous lead-free propellant formulations. The new formulations reduced or replaced the monobasic copper salicylate. The new formulations had improved aging characteristics. Their burn rates, however, were unacceptable for use in a 2.75 inch rocket. To compare aging characteristics, stabilizer depletion rates of RPD-422, AA2, M28, and RLC 470/6A were measured or taken from the literature. The data were fit to a kinetic model. The model contained first and zero order terms which allowed the stabilizer concentration to go to zero. In the model, only the concentration of the primary stabilizer was considered. Derivatives beyond the first nitrated or nitroso derivative of 2-NPDA were not considered. The rate constants were fit to the Arrhenius equation and extrapolated to lower temperatures. The time to complete stabilizer depletion was estimated using the kinetic model. The four propellants were compared and the RPD-422 depleted faster at 45 C than both A22 and M28. These types of predictions depend on the validity of the model and on confidence in the Arrhenius relationship holding at lower temperatures. At 45 C, the zero order portion of the model dominates the depletion rate.

  1. Comparative Treatment Failure Rates of Respiratory Fluoroquinolones or β-Lactam + Macrolide Versus β-Lactam Alone in the Treatment for Community-Acquired Pneumonia in Adult Outpatients

    PubMed Central

    Lee, Meng-Tse Gabriel; Lee, Shih-Hao; Chang, Shy-Shin; Chan, Ya-Lan; Pang, Laura; Hsu, Sue-Ming; Lee, Chien-Chang

    2015-01-01

    Abstract No comparative effectiveness study has been conducted for the following 3 antibiotics: respiratory fluoroquinolone, β-lactam, and β-lactam + advanced macrolide. To gain insights into the real-world clinical effectiveness of these antibiotics for community-acquired pneumonia in adult outpatients, our study investigated the treatment failure rates in 2 million representative participants from the National Health Informatics Project (NHIP) of Taiwan. A new-user cohort design was used to follow NHIP participants from January 2000 until December 2009. Treatment failure was defined by either one of the following events: a second antibiotic prescription, hospitalization due to CAP, an emergency department visit with a diagnosis of CAP, or 30-day nonaccident-related mortality. From 2006 to 2009, we identified 9256 newly diagnosed CAP outpatients, 1602 of whom were prescribed levofloxacin, 2100 were prescribed moxifloxacin, 5049 were prescribed β-lactam alone, and 505 were prescribed advanced macrolide + β-lactam. Compared with the β-lactam-based regimen, the propensity score-matched odds ratio for composite treatment failure was 0.81 (95% CI, 0.67–0.97) for moxifloxacin, 1.10 (95% CI, 0.90–1.35) for levofloxacin, and 0.95 (95% CI, 0.67–1.35) for macrolide +β-lactam. Moxifloxacin was associated with lower treatment failure rates compared with β-lactam alone, or levofloxacin in Taiwanese CAP outpatients. However, due to inherent limitations in our claims database, more randomized controlled trials are required before coming to a conclusion on which antibiotic is more effective for Taiwanese CAP outpatients. More population-based comparative effectiveness studies are also encouraged and should be considered as an integral piece of evidence in local CAP treatment guidelines. PMID:26426664

  2. A randomized comparison of the use of an optical compared with a rigid laryngoscope on the success rate of novices performing tracheal intubation.

    PubMed

    de Oliveira, Gildasio S; Fitzgerald, Paul C; Beckerly, Rena; McCarthy, Robert J

    2011-03-01

    Proficiency in tracheal intubation is a difficult skill to acquire, especially when using a rigid laryngoscope. We compared success in tracheal intubation by novices using an optical laryngoscope with that achieved with a rigid laryngoscope. After structured training in laryngoscopy and 5 consecutive successful intubation attempts using both the optical and rigid laryngoscope on a high-fidelity mannequin, trainees were randomly assigned to perform their first 2 tracheal intubations using either an optical or rigid laryngoscope using the standard Macintosh blade. The success rate for intubation was higher using the optical laryngoscope (23 of 30 attempts) compared with the rigid laryngoscope (8 of 30 attempts, P < 0.001). Intubation time was shorter using the optical laryngoscope (35 seconds; 95% confidence interval, 27-44 seconds) compared with the rigid laryngoscope (75 seconds; 95% confidence interval, 59-90 seconds) in successfully intubated patients (P < 0.001). Our study demonstrated greater successful tracheal intubation and reduced intubation time during the first two attempted intubations by novices using an optical compared with a rigid laryngoscope. PMID:21233492

  3. heavy ion acceleration at shocks

    NASA Astrophysics Data System (ADS)

    Shevchenko, V. I.; Galinsky, V.

    2009-12-01

    The theoretical study of alpha particle acceleration at a quasi-parallel shock due to interaction with Alfven waves self-consistently excited in both upstream and downstream regions was conducted using a scale-separation model [1]. The model uses conservation laws and resonance conditions to find where waves will be generated or dumped and hence particles will be pitch--angle scattered as well as the change of the wave energy due to instability or damping. It includes in consideration the total distribution function (the bulk plasma and high energy tail), so no any assumptions (e.g. seed populations, or some ad-hoc escape rate of accelerated particles) are required. In previous studies heavy ions were treated as perfect test particles, they only experienced the Alfven turbulence excited by protons and didn’t contribute to turbulence generation. In contrast to this approach, we consider the ion scattering on hydromagnetic turbulence generated by both protons and ions themselves. It is important for alpha particles with their relatively large mass-loading parameter that defines efficiency of the wave excitation by alpha particles. The energy spectra of alpha particles is found and compared with those obtained in test particle approximation. [1] Galinsky, V.L., and V.I. Shevchenko, Astrophys. J., 669, L109, 2007.

  4. Determination of convective diffusion heat/mass transfer rates to burner rig test targets comparable in size to cross-stream jet diameter

    NASA Technical Reports Server (NTRS)

    Gokoglu, S. A.; Santoro, G. J.

    1985-01-01

    Two sets of experiments have been performed to be able to predict the convective diffusion heat/mass transfer rates to a cylindrical target whose height and diameter are comparable to, but less than, the diameter of the circular cross-stream jet, thereby simulating the same geometric configuration as a typical burner rig test specimen located in the cross-stream of the combustor exit nozzle. The first set exploits the naphthalene sublimation technique to determine the heat/mass transfer coefficient under isothermal conditions for various flow rates (Reynolds numbers). The second set, conducted at various combustion temperatures and Reynolds numbers, utilized the temperature variation along the surface of the above-mentioned target under steady-state conditions to estimate the effect of cooling (dilution) due to the entrainment of stagnant room temperature air. The experimental information obtained is used to predict high temperature, high velocity corrosive salt vapor deposition rates in burner rigs on collectors that are geometrically the same. The agreement with preliminary data obtained from Na2SO4 vapor deposition experiments is found to be excellent.

  5. The role of exogenous electron donors for accelerating 2,4,6-trichlorophenol biotransformation and mineralization.

    PubMed

    Yan, Ning; Li, Rongjie; Xu, Hua; Li, Ling; Yang, Lihui; Zhang, Yongming; Liu, Rui; Rittmann, Bruce E

    2016-06-01

    2,4,6-Trichlorophenol (TCP) is a biologically recalcitrant compound, but its biodegradation via reductive dechlorination can be accelerated by adding an exogenous electron donor. In this work, acetate and formate were evaluated for their ability to accelerate TCP reductive dechlorination, as well to accelerate mono-oxygenation of TCP's reduction product, phenol. Acetate and formate accelerated TCP reductive dechlorination, and the impact was proportional to the number of electron equivalents released by oxidation of the donor: 8 e(-) equivalents per mol for acetate, compared to 2 e(-) eq per mol for formate. The acceleration phenomenon was similar for phenol mono-oxygenation, and this increased the rate of TCP mineralization. Compared to endogenous electron equivalents generated by phenol mineralization, the impact of exogenous electron donor was stronger on a per-equivalent basis. PMID:27084768

  6. Using accelerated life testing procedures to compare the relative sensitivity of rainbow trout and the federally listed threatened bull trout to three commonly used rangeland herbicides (picloram, 2,4-D, and clopyralid)

    USGS Publications Warehouse

    Fairchild, J.F.; Allert, A.; Sappington, L.S.; Nelson, K.J.; Valle, J.

    2008-01-01

    We conducted 96-h static acute toxicity studies to evaluate the relative sensitivity of juveniles of the threatened bull trout (Salvelinus confluentus) and the standard cold-water surrogate rainbow trout (Onchorhyncus mykiss) to three rangeland herbicides commonly used for controlling invasive weeds in the northwestern United States. Relative species sensitivity was compared using three procedures: standard acute toxicity testing, fractional estimates of lethal concentrations, and accelerated life testing chronic estimation procedures. The acutely lethal concentrations (ALC) resulting in 50% mortality at 96 h (96-h ALC50s) were determined using linear regression and indicated that the three herbicides were toxic in the order of picloram acid > 2,4-D acid > clopyralid acid. The 96-h ALC50 values for rainbow trout were as follows: picloram, 41 mg/L; 2.4-D, 707 mg/L; and clopyralid, 700 mg/L. The 96-h ALC50 values for bull trout were as follows: picloram, 24 mg/L; 2.4-D, 398 mg/L; and clopyralid, 802 mg/L. Fractional estimates of safe concentrations, based on 5% of the 96-h ALC50, were conservative (overestimated toxicity) of regression-derived 96-h ALC5 values by an order of magnitude. Accelerated life testing procedures were used to estimate chronic lethal concentrations (CLC) resulting in 1% mortality at 30 d (30-d CLC1) for the three herbicides: picloram (1 mg/L rainbow trout, 5 mg/L bull trout), 2,4-D (56 mg/L rainbow trout, 84 mg/L bull trout), and clopyralid (477 mg/L rainbow trout; 552 mg/L bull trout). Collectively, the results indicated that the standard surrogate rainbow trout is similar in sensitivity to bull trout. Accelerated life testing procedures provided cost-effective, statistically defensible methods for estimating safe chronic concentrations (30-d CLC1s) of herbicides from acute toxicity data because they use statistical models based on the entire mortality:concentration: time data matrix. ?? 2008 SETAC.

  7. Effects of eating breakfast compared with skipping breakfast on ratings of appetite and intake at subsequent meals in 8- to 10-y-old children123

    PubMed Central

    Kral, Tanja VE; Whiteford, Linda M; Heo, Moonseong; Faith, Myles S

    2011-01-01

    Background: Cross-sectional data indicate an inverse relation between breakfast consumption and child weight. It has been suggested that skipping breakfast may adversely affect appetite in children, which could lead to overeating later in the day. Objective: The aim of this study was to test the effects of consuming breakfast compared with omitting breakfast on appetite ratings and energy intake at subsequent meals in 8- to 10-y-old children. Design: Twenty-one children participated in 2 test visits during which they were served either a compulsory breakfast or no breakfast. On both visits, subjects were also served lunch, which was consumed ad libitum. Subjects rated their appetite throughout the morning; parents completed food records that captured children's intake for the remainder of the day. Results: There was no significant main effect of breakfast condition on energy intake at lunch (P = 0.36) or throughout the remainder of the day (P = 0.85). There was a significant main effect of breakfast condition (P = 0.04) on total daily energy intake, which indicated that on the day when the subjects did not eat breakfast, they consumed 362 fewer calories over the course of the day than when they did eat breakfast. On the day when no breakfast was served, subjects indicated that they were significantly hungrier, less full, and could consume more food before lunch than on the day when they did eat breakfast (P < 0.001). Conclusions: Omitting breakfast affected children's appetite ratings but not their energy intake at subsequent meals. The dissonance between children's subjective ratings of prospective consumption and their actual intake should be further examined. PMID:21084650

  8. Accelerator system and method of accelerating particles

    NASA Technical Reports Server (NTRS)

    Wirz, Richard E. (Inventor)

    2010-01-01

    An accelerator system and method that utilize dust as the primary mass flux for generating thrust are provided. The accelerator system can include an accelerator capable of operating in a self-neutralizing mode and having a discharge chamber and at least one ionizer capable of charging dust particles. The system can also include a dust particle feeder that is capable of introducing the dust particles into the accelerator. By applying a pulsed positive and negative charge voltage to the accelerator, the charged dust particles can be accelerated thereby generating thrust and neutralizing the accelerator system.

  9. Attention's Accelerator.

    PubMed

    Reinhart, Robert M G; McClenahan, Laura J; Woodman, Geoffrey F

    2016-06-01

    How do people get attention to operate at peak efficiency in high-pressure situations? We tested the hypothesis that the general mechanism that allows this is the maintenance of multiple target representations in working and long-term memory. We recorded subjects' event-related potentials (ERPs) indexing the working memory and long-term memory representations used to control attention while performing visual search. We found that subjects used both types of memories to control attention when they performed the visual search task with a large reward at stake, or when they were cued to respond as fast as possible. However, under normal circumstances, one type of target memory was sufficient for slower task performance. The use of multiple types of memory representations appears to provide converging top-down control of attention, allowing people to step on the attentional accelerator in a variety of high-pressure situations. PMID:27056975

  10. Comparative Study of Heart Rate Variability in Patients with Schizophrenia, Bipolar Disorder, Post-traumatic Stress Disorder, or Major Depressive Disorder

    PubMed Central

    Moon, Eunok; Kim, Do-Hyung; Hwang, Boram

    2013-01-01

    Objective Heart rate variability (HRV) changes as a function of psychiatric illness. This study aimed to evaluate HRV among patients with various psychiatric disorders. Methods The present study recruited patients with schizophrenia (n=35), bipolar disorder (n=41), post-traumatic stress disorder (PTSD; n=34), or major depressive disorder (n=34) as well as healthy controls (n=27). The time-domain analysis (the standard deviation of all RR intervals [SDNN] and the square root of the mean squared differences of successive normal sinus intervals [RMSSD]), the frequency-domain analysis (very low frequency, low frequency [LF], high frequency [HF], and total power [TP]), and a non-linear complexity measure the approximate entropy were computed. Results SDNN and HF were significantly reduced in patients with schizophrenia compared with healthy controls. SDNN, RMSSD, TP, LF, and HF were significantly reduced in bipolar patients compared with healthy controls. HF was significantly reduced in PTSD patients compared with healthy controls. Conclusion Our findings indicate that HRV is not sufficiently powerful to discriminate among various psychiatric illnesses. However, our results suggest that HRV, particularly HF, could be used as a tool for discriminating between psychiatric patients and healthy controls. PMID:24465250

  11. Superconducting rebalance acceleration and rate sensor

    NASA Technical Reports Server (NTRS)

    Torti, R.; Gerver, M.; Gondhalekar, V.; Maxwell, B.

    1994-01-01

    The goal of this program is the development of a high precision multisensor based on a high T(sub c) superconducting proof mass. The design of a prototype is currently underway. Key technical issues appear resolvable. High temperature superconductors have complicated, hysteretic flux dynamics but the forces on them can be linearly controlled for small displacements. Current data suggests that the forces on the superconductors decay over a short time frame and then stabilize, though very long term data is not available. The hysteretic force characteristics are substantial for large scale excursions, but do not appear to be an issue for the very small displacements required in this device. Sufficient forces can be exerted for non-contact suspension of a centimeter sized proof mass in a vacuum sealed nitrogen jacket cryostat. High frequency capacitive sensing using stripline technology will yield adequate position resolution for 0.1 micro-g measurements at 100 Hz. Overall, a reasonable cost, but very high accuracy, system is feasible with this technology.

  12. Two-beam accelerator

    SciTech Connect

    Selph, F.B.

    1984-09-01

    In the two-beam accelerator (TBA) concept, an electron linear accelerator structure is established in which two beams propagate. One is an intense low energy beam that is made to undergo free electron lasing to produce microwaves. These microwaves are then coupled to another part of the structure where they act to produce a high longitudinal electric gradient that is used to accelerate a second relatively low intensity electron beam to very high energies. The TBA was originally suggested by Sessler as a possible means for economically achieving linear collider energies of 100 GeV and above. Although still in a conceptual stage, the TBA is an inherently plausible concept that combines the free electron laser (FEL) with several well-known technologies - high current induction linacs, microwave waveguides, and traveling-wave linac structures - in a novel and interesting way. Two characteristics of the TBA that make it a particularly suitable candidate for achieving high energies are its ability to operate at higher frequencies than typical present-day linacs (say 30 GHz as compared with 3 GHz), and to be an efficient means for delivering power to a hitherto unattainable high-gradient structure (say 250 MV/m) that the higher frequency makes possible. These high accelerating gradients will permit much shorter linac structures for a given energy.

  13. Short Acceleration Times from Superdiffusive Shock Acceleration in the Heliosphere

    NASA Astrophysics Data System (ADS)

    Perri, S.; Zimbardo, G.

    2015-12-01

    The analysis of time profiles of particles accelerated at interplanetary shocks allows particle transport properties to be inferred. The frequently observed power-law decay upstream, indeed, implies a superdiffusive particle transport when the level of magnetic field variance does not change as the time interval from the shock front increases. In this context, a superdiffusive shock acceleration (SSA) theory has been developed, allowing us to make predictions of the acceleration times. In this work we estimate for a number of interplanetary shocks, including the solar wind termination shock, the acceleration times for energetic protons in the framework of SSA and we compare the results with the acceleration times predicted by standard diffusive shock acceleration. The acceleration times due to SSA are found to be much shorter than in the classical model, and also shorter than the interplanetary shock lifetimes. This decrease of the acceleration times is due to the scale-free nature of the particle displacements in the framework of superdiffusion. Indeed, very long displacements are possible, increasing the probability for particles far from the front of the shock to return, and short displacements have a high probability of occurrence, increasing the chances for particles close to the front to cross the shock many times.

  14. Maximal acceleration and radiative processes

    NASA Astrophysics Data System (ADS)

    Papini, Giorgio

    2015-08-01

    We derive the radiation characteristics of an accelerated, charged particle in a model due to Caianiello in which the proper acceleration of a particle of mass m has the upper limit 𝒜m = 2mc3/ℏ. We find two power laws, one applicable to lower accelerations, the other more suitable for accelerations closer to 𝒜m and to the related physical singularity in the Ricci scalar. Geometrical constraints and power spectra are also discussed. By comparing the power laws due to the maximal acceleration (MA) with that for particles in gravitational fields, we find that the model of Caianiello allows, in principle, the use of charged particles as tools to distinguish inertial from gravitational fields locally.

  15. Preimplantation genetic screening for all 24 chromosomes by microarray comparative genomic hybridization significantly increases implantation rates and clinical pregnancy rates in patients undergoing in vitro fertilization with poor prognosis

    PubMed Central

    Majumdar, Gaurav; Majumdar, Abha; Lall, Meena; Verma, Ishwar C.; Upadhyaya, Kailash C.

    2016-01-01

    CONTEXT: A majority of human embryos produced in vitro are aneuploid, especially in couples undergoing in vitro fertilization (IVF) with poor prognosis. Preimplantation genetic screening (PGS) for all 24 chromosomes has the potential to select the most euploid embryos for transfer in such cases. AIM: To study the efficacy of PGS for all 24 chromosomes by microarray comparative genomic hybridization (array CGH) in Indian couples undergoing IVF cycles with poor prognosis. SETTINGS AND DESIGN: A retrospective, case–control study was undertaken in an institution-based tertiary care IVF center to compare the clinical outcomes of twenty patients, who underwent 21 PGS cycles with poor prognosis, with 128 non-PGS patients in the control group, with the same inclusion criterion as for the PGS group. MATERIALS AND METHODS: Single cells were obtained by laser-assisted embryo biopsy from day 3 embryos and subsequently analyzed by array CGH for all 24 chromosomes. Once the array CGH results were available on the morning of day 5, only chromosomally normal embryos that had progressed to blastocyst stage were transferred. RESULTS: The implantation rate and clinical pregnancy rate (PR) per transfer were found to be significantly higher in the PGS group than in the control group (63.2% vs. 26.2%, P = 0.001 and 73.3% vs. 36.7%, P = 0.006, respectively), while the multiple PRs sharply declined from 31.9% to 9.1% in the PGS group. CONCLUSIONS: In this pilot study, we have shown that PGS by array CGH can improve the clinical outcome in patients undergoing IVF with poor prognosis. PMID:27382234

  16. Acceleration effects in solid propellant rocket motors

    NASA Technical Reports Server (NTRS)

    Langhenry, M. T.

    1986-01-01

    The performance variations due to acceleration loads imposed on spinning solid propellant rocket motors are investigated. The four potentially most significant modes of acceleration-induced phenomena are identified from a study of the literature and modeled. The four modes are a mechanical mode which deals with deformations of the propellant and case: a thermodynamic mode which covers acceleration-induced combustion phenomena; a stress mode which covers the stressed propellant's effect on burn rate; and a gas dynamic mode which deals with changes in gas flow in the chamber and through the nozzle. Simplified models of each mode are developed or taken from the literature and are added to an internal ballistics evaluation computer program. The resulting analysis is the first to include all of the modes. In order to do this an original analysis of the mechanical and stress modes was necessary. However, the analysis shows that the stress mode is not important for the circular perforated grains studied. The other effects are shown to have a significant influence on solid rocket motor performance. The magnitude of the different mode effects are such that one may not be ignored over the others as has been done in the past. The results of the analysis are compared to published rocket motor data. The comparisons indicate an erosive burning effect that is a function of spin rate. A qualitative explanation of the erosive effect is presented.

  17. Is the liver kinetic growth rate in ALPPS unprecedented when compared with PVE and living donor liver transplant? A multicentre analysis

    PubMed Central

    Croome, Kristopher P; Hernandez-Alejandro, Roberto; Parker, Maile; Heimbach, Julie; Rosen, Charles; Nagorney, David M

    2015-01-01

    Background The clinical perspective on hepatic growth is limited. The goal of the present study was to compare hepatic hypertrophy and the kinetic growth rate(KGR) in patients after the ALPPS (Associating Liver Partition with Portal Vein Ligation for Staged Hepatectomy) procedure, portal vein embolization (PVE) and living donor liver transplantation. Methods Volumetry and KGR of the future liver remnant (FLR) were compared from (15) patients undergoing ALPPS, (53) patients undergoing PVE, (90) recipients of living donor liver grafts and (93) donors of living donor liver grafts. Results The degree of hypertrophy was significantly greater after ALPPS (84.3 ± 7.8%) than after PVE (36.0 ± 27.2%) (P < 0.001). The KGR was also significantly greater for ALPPS [32.7 ± 13.6 cubic centimetres (cc)/day] (10.8 ± 4.5%/day) compared with PVE (4.4 ± 3.2 cc/day) (0.98 ± 0.75%/day) (P < 0.001). The FLR of living donor donors had the greatest degree of hypertrophy (107.5 ± 39.2%) and was greater than after ALPPS (P = 0.02), PVE (P < 0.001) and in living donor-recipient grafts (P < 0.001). KGR (cc/day) was greater in FLR of living donor donors compared with both ALPPS (P < 0.001) and PVE (P < 0.001). The KGR in patients undergoing ALPPS and living donor liver transplantation had a linear relationship with the size of FLR. Conclusion FLR hypertrophy and KGR were greater after ALPPS than PVE. However, the degree of hypertrophy after ALPPS is not unprecedented, as KGR in the FLR from living donor donors is equal to or greater than after ALPPS. The KGR of the FLR in patients after ALPPS and living donor donors correlates directly with the size of the FLR. PMID:25728543

  18. Experiences of Intimate Partner Violence and Subsequent Police Reporting Among Lesbian, Gay, Bisexual, Transgender, and Queer Adults in Colorado: Comparing Rates of Cisgender and Transgender Victimization.

    PubMed

    Langenderfer-Magruder, Lisa; Whitfield, Darren L; Walls, N Eugene; Kattari, Shanna K; Ramos, Daniel

    2016-03-01

    Research indicates that lesbian, gay, bisexual, transgender, and queer (LGBTQ) individuals are at high risk of victimization by others and that transgender individuals may be at even higher risk than their cisgender LGBQ peers. In examining partner violence in particular, extant literature suggests that LGBTQ individuals are at equal or higher risk of partner violence victimization compared with their heterosexual peers. As opposed to sexual orientation, there is little research on gender identity and partner violence within the LGBTQ literature. In the current study, the authors investigated intimate partner violence (IPV) in a large sample of LGBTQ adults (N = 1,139) to determine lifetime prevalence and police reporting in both cisgender and transgender individuals. Results show that more than one fifth of all participants ever experienced partner violence, with transgender participants demonstrating significantly higher rates than their cisgender peers. Implications focus on the use of inclusive language as well as future research and practice with LGBTQ IPV victims. PMID:25392392

  19. Comparative study of two anesthesia methods according to postoperative complications and one month mortality rate in the candidates of hip surgery

    PubMed Central

    Heidari, Saied Morteza; Soltani, Hasanali; Hashemi, Saied Jalal; Talakoub, Reihanak; Soleimani, Bahram

    2011-01-01

    BACKGROUND: Surgery for hip fractures can be done under general or neuraxial anesthesia. This study aimed to compare these two methods concerning their postoperative complications, duration of operation, hospitalization and the mortality rate within a period of one month after surgery. METHODS: 400 patients aged more than 30 years old and scheduled for elective operative fixation of fractured hip, randomly enrolled in two equal groups of general (GA) and neuraxial (NA) anesthesia. Hemoglobin level was measured before and 6 hours, 2, 3 and 5 days after the surgery. The intra and postoperative blood loss, duration of surgery, the severity of pain at the time of discharge from recovery and at the 2nd, 3rd and 5th postoperative days were recorded. Statistical analysis was performed using SPSS version 12.0 by Mann-Whitney, chi-square, and t tests. P < 0.05 was considered significant. RESULTS: Both groups were similar regarding age, weight, and gender ratio. There was no significant difference in baseline hemoglobin, duration of surgery, length of hospitalization before surgery and the type of surgery. The mean of intraoperative blood loss and visual analogue score (VAS) in recovery and at the 3rd postoperative day, and also the length of hospitalization after surgery were significantly less in neuraxial anesthesia group. Both groups showed a significant decrease in hemoglobin values on the 2nd and 3rd postoperative days comparing to the baseline (p < 0.001). CONCLUSIONS: The morbidity and mortality rates of patients undergoing hip surgery were similar in both methods of anesthesia, but postoperative pain, blood loss, and duration of hospitalization were more in patients undergoing general anesthesia. PMID:22091252

  20. Acute Response of Well-Trained Sprinters to a 100-m Race: Higher Sprinting Velocity Achieved With Increased Step Rate Compared With Speed Training.

    PubMed

    Otsuka, Mitsuo; Kawahara, Taisuke; Isaka, Tadao

    2016-03-01

    This study aimed to clarify the contribution of differences in step length and step rate to sprinting velocity in an athletic race compared with speed training. Nineteen well-trained male and female sprinters volunteered to participate in this study. Sprinting motions were recorded for each sprinter during both 100-m races and speed training (60-, 80-, and 100-m dash from a block start) for 14 days before the race. Repeated-measures analysis of covariance was used to compare the step characteristics and sprinting velocity between race and speed training, adjusted for covariates including race-training differences in the coefficients of restitution of the all-weather track, wind speed, air temperature, and sex. The average sprinting velocity to the 50-m mark was significantly greater in the race than in speed training (8.26 ± 0.22 m·s vs. 8.00 ± 0.70 m·s, p < 0.01). Although no significant difference was seen in the average step length to the 50-m mark between the race and speed training (1.81 ± 0.09 m vs. 1.80 ± 0.09 m, p = 0.065), the average step rate was significantly greater in the race than in speed training (4.56 ± 0.17 Hz vs. 4.46 ± 0.13 Hz, p < 0.01). These findings suggest that sprinters achieve higher sprinting velocity and can run with higher exercise intensity and more rapid motion during a race than during speed training, even if speed training was performed at perceived high intensity. PMID:26907837

  1. Cutting Balloon Angioplasty Versus Standard Balloon Angioplasty for Failing Infra-inguinal Vein Grafts: Comparative Study of Short- and Mid-Term Primary Patency Rates

    SciTech Connect

    Vikram, Raghunandan; Ross, Rose A.; Bhat, Rajesh; Griffiths, Gareth D.; Stonebridge, Peter A.; Houston, J. Graeme; Chakraverty, S.

    2007-07-15

    Purpose. To evaluate the results of a recent change in practice in our institution using cutting balloon angioplasty instead of standard balloon angioplasty as the primary treatment for failing infra-inguinal vein bypass grafts. Methods. In this nonrandomized cohort study with a historical control, failing infra-inguinal vein grafts were identified at duplex surveillance or clinical examination. Patients had confirmatory arteriography and balloon angioplasty at the same attendance. Interventions proximal or distal to the graft itself and prosthetic grafts were not included. Patients were entered into a duplex graft surveillance program. Initial assessment of technical success was duplex or improvement 4-6 weeks after the primary angioplasty. Results. Twenty-seven consecutive patients were treated with standard balloon angioplasty, then 11 consecutive patients were treated with cutting balloon angioplasty. Initial technical success was 74% for the standard balloon versus 82% for the cutting balloon. The primary patency rate at 6 months was 16/26 (62%) for standard balloon angioplasty and 8/10 (80%) for cutting balloon angioplasty (p = 0.44). The primary patency rate at 12 months was 9/25 (36%) for standard balloon angioplasty and 5/10 (50%) for cutting balloon angioplasty (p = 0.47). Conclusion. The use of cutting balloons for primary angioplasty of infra-inguinal vein grafts offers no definite advantage over standard balloon angioplasty in this institution or compared with patency rates after standard balloon angioplasty reported elsewhere. Larger multicenter studies would be required to demonstrate whether there was any real difference between the two techniques.

  2. Measuring ammonia emission rates from livestock buildings and manure stores—part 2: Comparative demonstrations of three methods on the farm

    NASA Astrophysics Data System (ADS)

    Dore, C. J.; Jones, B. M. R.; Scholtens, R.; Veld, J. W. H. Huis in't.; Burgess, L. R.; Phillips, V. R.

    Comparative demonstrations of three methods (flux sampling, external tracer ratio, and internal tracer ratio), were mounted in four real farm situations. A flux sampling method was demonstrated at a commercial dairy cow house (slurry-based), at a commercial piggery (straw-based), at a full-scale above-ground cylindrical slurry store (dairy cow slurry) and a full-scale earth-bank lagoon (pig slurry). An external tracer ratio method was demonstrated, in parallel with the flux sampling method, at the dairy cow house and at the above-ground slurry store. An internal tracer ratio method was demonstrated at the dairy cow house only. At the dairy cow house, the corrected emission rates from the flux sampling method and from the external tracer ratio method agreed to within the estimated experimental range, while the emission rate from the internal tracer ratio method was significantly lower. The overall conclusion of the study is that all three methods can have a useful role, the choice of which to deploy depending on the particular measurements needed in each case. The paper includes a table (No. 7) which indicates which is the recommended method when each of various considerations has top priority.

  3. Comparative analysis of viral genomes from acute and chronic hepatitis B reveals novel variants associated with a lower rate of chronicity.

    PubMed

    Chook, Jack Bee; Ngeow, Yun Fong; Khang, Tsung Fei; Ng, Kee Peng; Tiang, Yee Peng; Mohamed, Rosmawati

    2013-03-01

    Infection with the hepatitis B virus (HBV) may lead to an acute or chronic infection. It is generally accepted that the clinical outcome of infection depends on the balance between host immunity and viral survival strategies. In order to persist, the virus needs to have a high rate of replication and some immune-escape capabilities. Hence, HBVs lacking these properties are likely to be eliminated more rapidly by the host, leading to a lower rate of chronicity. To test this hypothesis, 177 HBV genomes from acute non-fulminant cases and 1,149 from chronic cases were retrieved from GenBank for comparative analysis. Selection of candidate nucleotides associated with the disease state was done using random guess cut-off and the Bonferroni correction. Five significant nucleotides were detected using this filtering step. Their predictive values were assessed using the support vector machine classification with five-fold cross-validation. The average prediction accuracy was 61% ± 1%, with a sensitivity of 24% ± 1%, specificity of 98% ± 1%, positive predictive value of 92% ± 4% and negative predictive value of 56% ± 1%. BCP/X, enhancer I and surface/polymerase variants were found to be associated almost exclusively with acute hepatitis. These HBV variants are novel potential markers for non-progression to chronic hepatitis. PMID:23297244

  4. Acceleration modules in linear induction accelerators

    NASA Astrophysics Data System (ADS)

    Wang, Shao-Heng; Deng, Jian-Jun

    2014-05-01

    The Linear Induction Accelerator (LIA) is a unique type of accelerator that is capable of accelerating kilo-Ampere charged particle current to tens of MeV energy. The present development of LIA in MHz bursting mode and the successful application into a synchrotron have broadened LIA's usage scope. Although the transformer model is widely used to explain the acceleration mechanism of LIAs, it is not appropriate to consider the induction electric field as the field which accelerates charged particles for many modern LIAs. We have examined the transition of the magnetic cores' functions during the LIA acceleration modules' evolution, distinguished transformer type and transmission line type LIA acceleration modules, and re-considered several related issues based on transmission line type LIA acceleration module. This clarified understanding should help in the further development and design of LIA acceleration modules.

  5. The global role of natural disaster fatalities in decision-making: statistics, trends and analysis from 116 years of disaster data compared to fatality rates from other causes

    NASA Astrophysics Data System (ADS)

    Daniell, James; Wenzel, Friedemann; McLennan, Amy; Daniell, Katherine; Kunz-Plapp, Tina; Khazai, Bijan; Schaefer, Andreas; Kunz, Michael; Girard, Trevor

    2016-04-01

    In this study, analysis is undertaken showing disaster fatalities trends from around the world using the CATDAT Natural Disaster and Socioeconomic Indicator databases from 1900-2015. Earthquakes have caused over 2.3 million fatalities since 1900; however absolute numbers of deaths caused by them have remained rather constant over time. However, floods have caused somewhere between 1.7 and 5.4 million fatalities, mostly in the earlier half of the 20th century (depending on the 1931 China floods). Storm and storm surges (ca. 1.3 million fatalities), on the other hand, have shown an opposite trend with increasing fatalities over the century (or a lack of records in the early 1900s). Earthquakes due to their sporadic nature, do not inspire investment pre-disaster. When looking at the investment in flood control vs. earthquakes, there is a marked difference in the total investment, which has resulted in a much larger reduction in fatalities. However, a key consideration for decision-makers in different countries around the world when choosing to implement disaster sensitive design is the risk of a natural disaster death, compared to other types of deaths in their country. The creation of empirical annualised ratios of earthquake, flood and storm fatalities from the year 1900 onwards vs. other methods of fatalities (cancer, diseases, accidents etc.) for each country using the CATDAT damaging natural disasters database is undertaken. On an annualised level, very few countries show earthquakes and other disaster types to be one of the highest probability methods for death. However, in particular years with large events, annual rates can easily exceed the total death count for a particular country. An example of this is Haiti, with the equivalent earthquake death rate in 2010 exceeding the total all-cause death rate in the country. Globally, fatality rates due to disasters are generally at least 1 order of magnitude lower than other causes such as heart disease. However, in

  6. Accelerating thinning of Kenai Peninsula glaciers, Alaska

    NASA Astrophysics Data System (ADS)

    VanLooy, J.; Forster, R.; Ford, A.

    2006-11-01

    Temperate mountain glaciers are thinning at high rates and significantly contributing to sea level rise. Due to these glaciers' remote locations, remote sensing and digital elevation models (DEMs) are an effective way to calculate their thinning rates and contribution to sea level rise. Comparisons of 1950s United States Geological Survey (USGS) and 2000 Shuttle Radar Topographic Mission (SRTM) DEMs with DEMs produced from Lidar profiles of glacier center-lines indicate thinning rates from the mid-1990s to 1999 (-0.72 +/- 0.13 m y-1) accelerated by a factor of 1.5 as compared with 1950 to mid-1990s (-0.47 +/- 0.01 m y-1) for glaciers on the Harding Icefield. Overall, comparison of USGS and SRTM DEMs indicate the Harding Icefield and Grewingk-Yalik Glacier Complex, Alaska, are thinning -0.61 +/- 0.12 m y-1 from 1950 to 1999.

  7. A Comparative Study of Sonographic Grading of Renal Parenchymal Changes and Estimated Glomerular Filtration Rate (eGFR) using Modified Diet in Renal Disease Formula

    PubMed Central

    Shivalli, Siddharudha; Pai, B.H. Santhosh; Acharya, Koteshwara Devadasa; Gopalakrishnan, Ravichandra; Srikanth, Vivek; Reddy, Vishwanath; Haris, Arafat

    2016-01-01

    Introduction The sonographic findings are of help in evaluating the nephrological diseases. Glomerular filtration rate is another parameter for assessing the reserved renal function and an indicator of prognosis. In clinical practice GFR estimation (eGFR) is done by using a mathematical formula. In our study, we compared the sonographic grading of renal parenchymal changes with eGFR calculated using Modified Diet in Renal Diseases formula based on serum creatinine, age, gender and ethnicity. Aim To evaluate the relevance of sonographic grading of renal parenchymal changes in assessing the severity of the renal disease and comparing it to the eGFR calculated using MDRD formula based on the age, gender and serum creatinine value of the patient. Materials and Methods The adult patients with suspected kidney disease referred for sonography of abdomen were our study participants. As per our study design following strict inclusion and exclusion criteria, patients were selected as study participants and for each of the patient’s renal parenchymal status, serum creatinine, age, gender and ethnicity were documented. Results A total of 70 patients were our study participants, out of which 67.1% were males and 32.9% were females. Our study showed a linear correlation between sonographic grading of renal parenchymal changes with eGFR. Conclusion We conclude that by evaluating the kidneys with sonography and calculating eGFR using MDRD formula the renal status will be more accurately interpreted. PMID:27042555

  8. Development of new method and protocol for cryopreservation related to embryo and oocytes freezing in terms of fertilization rate: A comparative study including review of literature

    PubMed Central

    Barik, Mayadhar; Bajpai, Minu; Patnaik, Santosh; Mishra, Pravash; Behera, Priyamadhaba; Dwivedi, Sada Nanda

    2016-01-01

    Background: Cryopreservation is basically related to meritorious thin samples or small clumps of cells that are cooled quickly without loss. Our main objective is to establish and formulate an innovative method and protocol development for cryopreservation as a gold standard for clinical uses in laboratory practice and treatment. The knowledge regarding usefulness of cryopreservation in clinical practice is essential to carry forward the clinical practice and research. Materials and Methods: We are trying to compare different methods of cryopreservation (in two dozen of cells) at the same time we compare the embryo and oocyte freezing interms of fertilization rate according to the International standard protocol. Results: The combination of cryoprotectants and regimes of rapid cooling and rinsing during warming often allows successful cryopreservation of biological materials, particularly cell suspensions or thin tissue samples. Examples include semen, blood, tissue samples like tumors, histological cross-sections, human eggs and human embryos. Although presently many studies have reported that the children born from frozen embryos or “frosties,” show consistently positive results with no increase in birth defects or development abnormalities is quite good enough and similar to our study (50–85%). Conclusions: We ensure that cryopreservation technology provided useful cell survivability, tissue and organ preservation in a proper way. Although it varies according to different laboratory conditions, it is certainly beneficial for patient's treatment and research. Further studies are needed for standardization and development of new protocol. PMID:27512686

  9. Homogeneous nucleation rate measurements of 1-butanol in helium: a comparative study of a thermal diffusion cloud chamber and a laminar flow diffusion chamber.

    PubMed

    Brus, David; Hyvärinen, Antti-Pekka; Zdímal, Vladimír; Lihavainen, Heikki

    2005-06-01

    Isothermal homogeneous nucleation rates of 1-butanol were measured both in a thermal diffusion cloud chamber and in a laminar flow diffusion chamber built recently at the Institute of Chemical Process Fundamentals, Academy of Sciences of the Czech Republic, Prague, Czech Republic. The chosen system 1-butanol-helium can be studied reasonably well in both devices, in the overlapping range of temperatures. The results were compared with those found in the literature and those measured by Lihavainen in a laminar flow diffusion chamber of a similar design. The same isotherms measured with the thermal diffusion cloud chamber occur at highest saturation ratios of the three devices. Isotherms measured with the two laminar flow diffusion chambers are reasonably close together; the measurements by Lihavainen occur at lowest saturation ratios. The temperature dependences observed were similar in all three devices. The molecular content of critical clusters was calculated using the nucleation theorem and compared with the Kelvin equation. Both laminar flow diffusion chambers provided very similar sizes slightly above the Kelvin equation, whereas the thermal diffusion cloud chamber suggests critical cluster sizes significantly smaller. The results found elsewhere in the literature were in reasonable agreement with our results. PMID:15974753

  10. Comparing recidivism rates of treatment responders/nonresponders in a sample of 413 child molesters who had completed community-based sex offender treatment in the United kingdom.

    PubMed

    Beech, Anthony R; Mandeville-Norden, Rebecca; Goodwill, Alasdair

    2012-02-01

    Analysis of psychometric data from a sample of 413 child molesters who had completed a U.K. probation-based sex offender treatment program was carried out to assess (a) the effectiveness of therapy in the short term and (b) the longer term implications of treatment in relation to sexual recidivism. It was found that 12% (51 offenders) of the sample had recidivated within 2 to 4 years. Of these recidivists, 86% (44 offenders) had been reconvicted for a sexually related offense. One hundred thirty-five offenders (33%) demonstrated a treated profile (i.e., demonstrated no offense-specific problems and few, or no, socioaffective problems at the posttreatment stage). This group was compared with a sample of offenders deemed as not responding to treatment, matched by their levels of pretreatment risk/need. It was found that a significantly smaller proportion (n = 12, 9%) of treatment responders had recidivated, compared to the treatment nonresponders (n = 20, 15%), indicating a 40% reduction in recidivism in those who had responded to treatment (effect size = .18). Matching length of treatment to the offenders' level of pretreatment risk/need (i.e., higher risk/treatment-need offenders typically undertook longer treatment) reduced the rate of recidivism among this group to the level of recidivism observed among the lower risk/need offenders. PMID:21187301

  11. How to compare scores from different depression scales: equating the Patient Health Questionnaire (PHQ) and the ICD-10-Symptom Rating (ISR) using Item Response Theory.

    PubMed

    Fischer, H Felix; Tritt, Karin; Klapp, Burghard F; Fliege, Herbert

    2011-12-01

    A wide range of questionnaires for measuring depression are available. Item Response Theory models can help to evaluate the questionnaires exceeding the boundaries of Classical Test Theory and provide an opportunity to equate the questionnaires. In this study after checking for unidimensionality, a General Partial Credit Model was applied to data from two different depression scales [Patient Health Questionnaire (PHQ-9) and ICD-10-Symptom Rating (ISR)] obtained in clinical settings from a consecutive sample, including 4517 observations from a total of 2999 inpatients and outpatients of a psychosomatic clinic. The precision of each questionnaire was compared and the model was used to transform scores based on the assumed underlying latent trait. Both instruments were constructed to measure the same construct and their estimates of depression severity are highly correlated. Our analysis showed that the predicted scores provided by the conversion tables are similar to the observed scores in a validation sample. The PHQ-9 and ISR depression scales measure depression severity across a broad range with similar precision. While the PHQ-9 shows advantages in measuring low or high depression severity, the ISR is more parsimonious and also suitable for clinical purposes. Furthermore, the equation tables derived in this study enhance the comparability of studies using either one of the instruments, but due to substantial statistical spread the comparison of individual scores is imprecise. PMID:22021205

  12. Rail accelerator research at Lewis Research Center

    NASA Technical Reports Server (NTRS)

    Kerslake, W. R.; Cybyk, B. Z.

    1982-01-01

    A rail accelerator was chosen for study as an electromagnetic space propulsion device because of its simplicity and existing technology base. The results of a mission feasibility study using a large rail accelerator for direct launch of ton-size payloads from the Earth's surface to space, and the results of initial tests with a small, laboratory rail accelerator are presented. The laboratory rail accelerator has a bore of 3 by 3 mm and has accelerated 60 mg projectiles to velocities of 300 to 1000 m/s. Rail materials of Cu, W, and Mo were tested for efficiency and erosion rate.

  13. Progress on plasma accelerators

    SciTech Connect

    Chen, P.

    1986-05-01

    Several plasma accelerator concepts are reviewed, with emphasis on the Plasma Beat Wave Accelerator (PBWA) and the Plasma Wake Field Accelerator (PWFA). Various accelerator physics issues regarding these schemes are discussed, and numerical examples on laboratory scale experiments are given. The efficiency of plasma accelerators is then revealed with suggestions on improvements. Sources that cause emittance growth are discussed briefly.

  14. Proton Acceleration at Oblique Shocks

    NASA Astrophysics Data System (ADS)

    Galinsky, V. L.; Shevchenko, V. I.

    2011-06-01

    Acceleration at the shock waves propagating oblique to the magnetic field is studied using a recently developed theoretical/numerical model. The model assumes that resonant hydromagnetic wave-particle interaction is the most important physical mechanism relevant to motion and acceleration of particles as well as to excitation and damping of waves. The treatment of plasma and waves is self-consistent and time dependent. The model uses conservation laws and resonance conditions to find where waves will be generated or damped, and hence particles will be pitch-angle-scattered. The total distribution is included in the model and neither introduction of separate population of seed particles nor some ad hoc escape rate of accelerated particles is needed. Results of the study show agreement with diffusive shock acceleration models in the prediction of power spectra for accelerated particles in the upstream region. However, they also reveal the presence of spectral break in the high-energy part of the spectra. The role of the second-order Fermi-like acceleration at the initial stage of the acceleration is discussed. The test case used in the paper is based on ISEE-3 data collected for the shock of 1978 November 12.

  15. PROTON ACCELERATION AT OBLIQUE SHOCKS

    SciTech Connect

    Galinsky, V. L.; Shevchenko, V. I.

    2011-06-20

    Acceleration at the shock waves propagating oblique to the magnetic field is studied using a recently developed theoretical/numerical model. The model assumes that resonant hydromagnetic wave-particle interaction is the most important physical mechanism relevant to motion and acceleration of particles as well as to excitation and damping of waves. The treatment of plasma and waves is self-consistent and time dependent. The model uses conservation laws and resonance conditions to find where waves will be generated or damped, and hence particles will be pitch-angle-scattered. The total distribution is included in the model and neither introduction of separate population of seed particles nor some ad hoc escape rate of accelerated particles is needed. Results of the study show agreement with diffusive shock acceleration models in the prediction of power spectra for accelerated particles in the upstream region. However, they also reveal the presence of spectral break in the high-energy part of the spectra. The role of the second-order Fermi-like acceleration at the initial stage of the acceleration is discussed. The test case used in the paper is based on ISEE-3 data collected for the shock of 1978 November 12.

  16. Rates of particle size reduction and passage are faster for legume compared with cool-season grass, resulting in lower rumen fill and less effective fiber.

    PubMed

    Kammes, K L; Allen, M S

    2012-06-01

    Effects of forage family on rates of particle size reduction in, and passage from, the rumen and the relationship of these effects with preliminary dry matter intake (pDMI) were evaluated using 13 ruminally and duodenally cannulated Holstein cows in a crossover design with a 14-d preliminary period and two 18-d treatment periods. During the preliminary period, pDMI of individual cows ranged from 19.6 to 29.5 kg/d (mean = 25.9 kg/d). Experimental treatments were diets containing either a) alfalfa silage (AL) or b) orchardgrass silage (OG) as the sole forage. Silages were chopped to 10-mm theoretical length of cut and contained 42.3 and 58.2% neutral detergent fiber (NDF) for alfalfa and orchardgrass, respectively. Both diets contained approximately 25% forage NDF and 30% total NDF. Feed, orts, rumen, and duodenal samples were wet sieved to fractionate particles above (large) and below (small) 2.36 mm. Indigestible NDF (iNDF) was used as a flow marker. Preliminary DMI, an index of nutrient demand, was determined during the last 4 d of the preliminary period when cows were fed a common diet and used as a covariate. Main effects of forage family and their interaction with pDMI were tested by ANOVA. Approximately 75% of the NDF consumed was large and 25% was small for both treatments, but cows fed AL consumed more iNDF and less potentially digestible NDF (pdNDF) than cows fed OG. The AL diet increased the reduction rate (large to small) compared with OG despite less rumination per unit of forage NDF for AL than OG, suggesting alfalfa NDF was more fragile than orchardgrass NDF. Over 55% of particles in the rumen were below 2.36 mm for AL and OG, indicating that particle size was not a limiting constraint to passage. Passage rates (k(p)) of large iNDF and large pdNDF were similar for AL and OG, but AL increased k(p) of large pdNDF and OG decreased it as pDMI increased. The AL diet increased k(p) of small iNDF and small pdNDF compared with OG, resulting in lower rumen fill

  17. Dosing Accuracy and Insulin Flow Rate Characteristics of a New Disposable Insulin Pen, FlexTouch, Compared with SoloSTAR

    PubMed Central

    Bohnet, Janine; Schmitz, Mario; Kamlot, Stefan; Mona, Abdel-Tawab

    2013-01-01

    Background The introduction of the FlexTouch® (FT; Novo Nordisk; insulin aspart), a prefilled insulin pen with a spring-loaded mechanism, has created more insulin pen options. The present study compared the dosing accuracy of the FT with that of the manually operated SoloSTAR® (SS; Sanofi; insulin glulisine). The volumetric flow rate of insulin delivery with the FT was also evaluated. Methods Thirty unused pens from one batch of each pen type were used to test dosing accuracy at minimum (1 U), mid (40 U), and maximum dose (80 U). Statistical analysis was performed using Student’s t-test. Insulin flow was determined with 20 FT pens ejecting 80 U three times per pen using a mass flow meter. Results Both insulin pens revealed excellent dosing accuracy, delivering all doses within the limits set by ISO 11608-1:2000. The average relative deviation of the actual dose from the target dose was +6.86% and +3.87% at the minimum, -0.72% and -1.01% at the mid, and -0.68% and -1.06% at the maximum dose for the SS and FT, respectively. The difference at maximum dose was statistically significant (p = .006) in favor of the SS. The FT showed a mean maximum flow rate of 15.61 U/s, with 80.52% of the total dose delivered at an injection speed exceeding 10 U/s. Conclusions This study demonstrated excellent dosing accuracy for the SS and FT at all tested dosage levels. The average maximum injection speed of the FT was considerably higher than the usual range of 6–10 U/s assumed for a smooth and painless injection. Further investigations should confirm the clinical relevance. PMID:23911185

  18. Magnitude of placebo response and response variance in antidepressant clinical trials using structured, taped and appraised rater interviews compared to traditional rating interviews.

    PubMed

    Khan, Arif; Faucett, James; Brown, Walter A

    2014-04-01

    The high failure rate of antidepressant clinical trials is due in part to a high magnitude of placebo response and considerable variance in placebo response. In some recent trials enhanced patient interview techniques consisting of Structured Interview Guide for the Montgomery-Asberg Depression Rating Scale (SIGMA) interviews, audiotaping of patient interviews and 'central' appraisal with Rater Applied Performance Scale (RAPS) criteria have been implemented in the hope of increasing reliability and thus reducing the placebo response. However, the data supporting this rationale for a change in patient interview technique are sparse. We analyzed data from depressed patients assigned to placebo in antidepressant clinical trials conducted at a single research site between 2008 and 2012. Three trials included 34 depressed patients undergoing SIGMA depression interviews with taping and RAPS appraisal and 4 trials included 128 depressed patients using traditional interview methods. Using patient level data we assessed the mean decrease in total MADRS scores and the variability of the decrease in MADRS scores in trials using SIGMA interviews versus trials using traditional interviews. Mean decrease in total MADRS score was significantly higher in the 3 trials that used SIGMA interviews compared to the 4 trials using traditional interviews (M = 13.0 versus 8.3, t(df = 160) = 2.04, p = 0.047). Furthermore, trials using SIGMA had a larger magnitude of response variance based on Levene's test for equality of variance (SD = 12.3 versus 9.4, F = 7.3, p = 0.008). The results of our study suggest that enhanced patient interview techniques such as SIGMA interviews, audiotaping and RAPS appraisal may not result in the intended effect of reducing the magnitude of placebo response and placebo variance. PMID:24477068

  19. Exercise Training During +Gz Acceleration

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.; Chou, J. L.; Simonson, S. R.; Jackson, C. G. R.; Barnes, P. R.

    1999-01-01

    The overall purpose is to study the effect of passive (without exercise) and active (with exercise) +Gz (head-to-foot) acceleration training, using a short-arm (1.9m radius) centrifuge, on post- training maximal oxygen uptake (VO2 max, work capacity) and 70 deg head-up tilt (orthostatic) tolerance in ambulatory subjects to test the hypothesis that (a) both passive and active acceleration training will improve post-training tilt-tolerance, and (b) there will be no difference in tilt-tolerance between passive and active exercise acceleration training because increased hydrostatic and blood pressures, rather than increased muscular metabolism, will provide the major adaptive stimulus. The purpose of the pilot study was to test the hypothesis that there would be no significant difference in the metabolic responses (oxygen uptake, heart rate, pulmonary ventilation, or respiratory exchange ratio) during supine exercise with moderate +Gz acceleration.

  20. Progress of Laser-Driven Plasma Accelerators

    NASA Astrophysics Data System (ADS)

    Nakajima, Kazuhisa

    2007-07-01

    There is a great interest worldwide in plasma accelerators driven by ultra-intense lasers which make it possible to generate ultra-high gradient acceleration and high quality particle beams in a much more compact size compared with conventional accelerators. A frontier research on laser and plasma accelerators is focused on high energy electron acceleration and ultra-short X-ray and Tera Hertz radiations as their applications. These achievements will provide not only a wide range of sciences with benefits of a table-top accelerator but also a basic science with a tool of ultrahigh energy accelerators probing an unknown extremely microscopic world. Harnessing the recent advance of ultra-intense ultra-short pulse lasers, the worldwide research has made a tremendous breakthrough in demonstrating high-energy high-quality particle beams in a compact scale, so called "dream beams on a table top", which represents monoenergetic electron beams from laser wakefield accelerators and GeV acceleration by capillary plasma-channel laser wakefield accelerators. This lecture reviews recent progress of results on laser-driven plasma based accelerator experiments to quest for particle acceleration physics in intense laser-plasma interactions and to present new outlook for the GeV-range high-energy laser plasma accelerators.

  1. Progress of Laser-Driven Plasma Accelerators

    SciTech Connect

    Nakajima, Kazuhisa

    2007-07-11

    There is a great interest worldwide in plasma accelerators driven by ultra-intense lasers which make it possible to generate ultra-high gradient acceleration and high quality particle beams in a much more compact size compared with conventional accelerators. A frontier research on laser and plasma accelerators is focused on high energy electron acceleration and ultra-short X-ray and Tera Hertz radiations as their applications. These achievements will provide not only a wide range of sciences with benefits of a table-top accelerator but also a basic science with a tool of ultrahigh energy accelerators probing an unknown extremely microscopic world.Harnessing the recent advance of ultra-intense ultra-short pulse lasers, the worldwide research has made a tremendous breakthrough in demonstrating high-energy high-quality particle beams in a compact scale, so called ''dream beams on a table top'', which represents monoenergetic electron beams from laser wakefield accelerators and GeV acceleration by capillary plasma-channel laser wakefield accelerators. This lecture reviews recent progress of results on laser-driven plasma based accelerator experiments to quest for particle acceleration physics in intense laser-plasma interactions and to present new outlook for the GeV-range high-energy laser plasma accelerators.

  2. Mortality rates at 10 years after metal-on-metal hip resurfacing compared with total hip replacement in England: retrospective cohort analysis of hospital episode statistics

    PubMed Central

    Kendal, Adrian R; Prieto-Alhambra, Daniel; Arden, Nigel K; Judge, Andrew

    2013-01-01

    Objectives To compare 10 year mortality rates among patients undergoing metal-on-metal hip resurfacing and total hip replacement in England. Design Retrospective cohort study. Setting English hospital episode statistics database linked to mortality records from the Office for National Statistics. Population All adults who underwent primary elective hip replacement for osteoarthritis from April 1999 to March 2012. The exposure of interest was prosthesis type: cemented total hip replacement, uncemented total hip replacement, and metal-on-metal hip resurfacing. Confounding variables included age, sex, Charlson comorbidity index, rurality, area deprivation, surgical volume, and year of operation. Main outcome measures All cause mortality. Propensity score matching was used to minimise confounding by indication. Kaplan-Meier plots estimated the probability of survival up to 10 years after surgery. Multilevel Cox regression modelling, stratified on matched sets, described the association between prosthesis type and time to death, accounting for variation across hospital trusts. Results 7437 patients undergoing metal-on-metal hip resurfacing were matched to 22 311 undergoing cemented total hip replacement; 8101 patients undergoing metal-on-metal hip resurfacing were matched to 24 303 undergoing uncemented total hip replacement. 10 year rates of cumulative mortality were 271 (3.6%) for metal-on-metal hip resurfacing versus 1363 (6.1%) for cemented total hip replacement, and 239 (3.0%) for metal-on-metal hip resurfacing versus 999 (4.1%) for uncemented total hip replacement. Patients undergoing metal-on-metal hip resurfacing had an increased survival probability (hazard ratio 0.51 (95% confidence interval 0.45 to 0.59) for cemented hip replacement; 0.55 (0.47 to 0.65) for uncemented hip replacement). There was no evidence for an interaction with age or sex. Conclusions Patients with hip osteoarthritis undergoing metal-on-metal hip resurfacing have reduced mortality in

  3. Variations of high frequency parameter of heart rate variability following osteopathic manipulative treatment in healthy subjects compared to control group and sham therapy: randomized controlled trial

    PubMed Central

    Ruffini, Nuria; D'Alessandro, Giandomenico; Mariani, Nicolò; Pollastrelli, Alberto; Cardinali, Lucia; Cerritelli, Francesco

    2015-01-01

    Context: Heart Rate Variability (HRV) indicates how heart rate changes in response to inner and external stimuli. HRV is linked to health status and it is an indirect marker of the autonomic nervous system (ANS) function. Objective: To investigate the influence of osteopathic manipulative treatment (OMT) on cardiac autonomic modulation in healthy subjects, compared with sham therapy and control group. Methods: Sixty-six healthy subjects, both male and female, were included in the present 3-armed randomized placebo controlled within subject cross-over single blinded study. Participants were asymptomatic adults (26.7 ± 8.4 y, 51% male, BMI 18.5 ± 4.8), both smokers and non-smokers and not on medications. At enrollment subjects were randomized in three groups: A, B, C. Standardized structural evaluation followed by a patient need-based osteopathic treatment was performed in the first session of group A and in the second session of group B. Standardized evaluation followed by a protocoled sham treatment was provided in the second session of group A and in the first session of group B. No intervention was performed in the two sessions of group C, acting as a time-control. The trial was registered on clinicaltrials.gov identifier: NCT01908920. Main Outcomes Measures: HRV was calculated from electrocardiography before, during and after the intervention, for a total amount time of 25 min and considering frequency domain as well as linear and non-linear methods as outcome measures. Results: OMT engendered a statistically significant increase of parasympathetic activity, as shown by High Frequency power (p < 0.001), expressed in normalized and absolute unit, and possibly decrease of sympathetic activity, as revealed by Low Frequency power (p < 0.01); results also showed a reduction of Low Frequency/High Frequency ratio (p < 0.001) and Detrended fluctuation scaling exponent (p < 0.05). Conclusions: Findings suggested that OMT can influence ANS activity increasing

  4. Flame acceleration in channels with obstacles in the deflagration-to-detonation transition

    SciTech Connect

    Valiev, Damir; Bychkov, Vitaly; Akkerman, V'yacheslav; Law, Chung K.; Eriksson, Lars-Erik

    2010-05-15

    It was demonstrated recently in Bychkov et al. [Bychkov et al., Phys. Rev. Lett. 101 (2008) 164501], that the physical mechanism of flame acceleration in channels with obstacles is qualitatively different from the classical Shelkin mechanism. The new mechanism is much stronger, and is independent of the Reynolds number. The present study provides details of the theory and numerical modeling of the flame acceleration. It is shown theoretically and computationally that flame acceleration progresses noticeably faster in the axisymmetric cylindrical geometry as compared to the planar one, and that the acceleration rate reduces with increasing Mach number and thereby the gas compressibility. Furthermore, the velocity of the accelerating flame saturates to a constant value that is supersonic with respect to the wall. The saturation state can be correlated to the Chapman-Jouguet deflagration as well as the fast flames observed in experiments. The possibility of transition from deflagration-to-detonation in the obstructed channels is demonstrated. (author)

  5. A preliminary investigation comparing one and eight channels at fast and slow rates on music appraisal in adults with cochlear implants.

    PubMed

    Tyler, R S; Gfeller, K; Mehr, M A

    2000-09-01

    Music perception is important to cochlear implant patients, but little effort has been devoted to improving signal processing for music. In this preliminary investigation, we probed the importance of number of channels and stimulus rate. We asked eight users of the Clarion cochlear implant to rate music quality on a scale from 0 to 100 on three different types of music (country and western, pop and classical). Patients rated eight- and one-channel processors running at a fast and slow rate. The stimulus rate was 200 pps for the slow rate. For the eight-channel condition, the fast rate varied from 394 to 765 pps. For the one-channel condition, the fast rate varied from 2601 to 4335 pps. Results indicated that the eight-channel condition was uniformly rated higher than the one-channel condition. However, the results for stimulus rate were less clear. No patients assigned higher ratings with the slow rate, but only three subjects assigned higher ratings with the fast rate. We conclude that music perception can be influenced and probably improved by signal processing. The number of channels, or perhaps spectral representation, is critical for music appreciation by cochlear implant recipients. PMID:18791996

  6. Dosimetry analyses comparing high-dose-rate brachytherapy, administered as monotherapy for localized prostate cancer, with stereotactic body radiation therapy simulated using CyberKnife.

    PubMed

    Fukuda, Shoichi; Seo, Yuji; Shiomi, Hiroya; Yamada, Yuji; Ogata, Toshiyuki; Morimoto, Masahiro; Konishi, Koji; Yoshioka, Yasuo; Ogawa, Kazuhiko

    2014-11-01

    The purpose of this study was to perform dosimetry analyses comparing high-dose-rate brachytherapy (HDR-BT) with simulated stereotactic body radiotherapy (SBRT). We selected six consecutive patients treated with HDR-BT monotherapy in 2010, and a CyberKnife SBRT plan was simulated for each patient using computed tomography images and the contouring set used in the HDR-BT plan for the actual treatment, but adding appropriate planning target volume (PTV) margins for SBRT. Then, dosimetric profiles for PTVs of the rectum, bladder and urethra were compared between the two modalities. The SBRT plan was more homogenous and provided lower dose concentration but better coverage for the PTV. The maximum doses in the rectum were higher in the HDR-BT plans. However, the HDR-BT plan provided a sharper dose fall-off around the PTV, resulting in a significant and considerable difference in volume sparing of the rectum with the appropriate PTV margins added for SBRT. While the rectum D5cm(3) for HDR-BT and SBRT was 30.7 and 38.3 Gy (P < 0.01) and V40 was 16.3 and 20.8 cm(3) (P < 0.01), respectively, SBRT was significantly superior in almost all dosimetric profiles for the bladder and urethra. These results suggest that SBRT as an alternative to HDR-BT in hypofractionated radiotherapy for prostate cancer might have an advantage for bladder and urethra dose sparing, but for the rectum only when proper PTV margins for SBRT are adopted. PMID:24957754

  7. The Combination of Valacyclovir with an Anti-TNF Alpha Antibody Increases Survival Rate Compared to Antiviral Therapy Alone in a Murine Model of Herpes Simplex Virus Encephalitis.

    PubMed

    Boivin, Nicolas; Menasria, Rafik; Piret, Jocelyne; Rivest, Serge; Boivin, Guy

    2013-10-24

    The added benefit of combining valacyclovir (VACV), an antiviral agent, with etanercept (ETA), an anti-tumor necrosis factor alpha (TNF-α) antibody, for the treatment of herpes simplex virus type 1 (HSV-1) encephalitis (HSE) was evaluated in a mouse model. BALB/c mice were infected intranasally with 1.85x10(4) plaque forming units of HSV-1. Groups of mice received a single intraperitoneal injection of vehicle or ETA (400 μg/mouse) on day 3 post-infection combined or not with VACV (1 mg/ml of drinking water) from days 3 to 21 post-infection. On day 5 post-infection, groups of mice were sacrificed for determination of viral DNA load, detection of ETA in brain homogenates and for in situ hybridization. The survival rate of mice was significantly increased when VACV was administered in combination with ETA (38.5% for VACV vs 78.6% for combined treatment; P=0.04) although VACV or ETA alone had no significant effect compared to the vehicle. The benefit of combined therapy was still present when treatment was delayed until day 4 post-infection. The viral DNA load was significantly reduced in mice treated with VACV alone (P<0.01) or combined with ETA (P<0.05) compared to the uninfected group whereas ETA alone had no effect. These results reinforce the notion that both virus-induced and immune-related mechanisms participate in the pathogenesis of HSE and suggest that potent antiviral agent could be combined with immune-based therapy, such as a TNF-α inhibitor, to improve prognosis of HSE. PMID:24513309

  8. The combination of valacyclovir with an anti-TNF alpha antibody increases survival rate compared to antiviral therapy alone in a murine model of herpes simplex virus encephalitis.

    PubMed

    Boivin, Nicolas; Menasria, Rafik; Piret, Jocelyne; Rivest, Serge; Boivin, Guy

    2013-12-01

    The added benefit of combining valacyclovir (VACV), an antiviral agent, with etanercept (ETA), an anti-tumor necrosis factor alpha (TNF-α) antibody, for the treatment of herpes simplex virus type 1 (HSV-1) encephalitis (HSE) was evaluated in a mouse model. BALB/c mice were infected intranasally with 1.85 × 104 plaque forming units of HSV-1. Groups of mice received a single intraperitoneal injection of vehicle or ETA (400 μg/mouse) on day 3 post-infection combined or not with VACV (1 mg/ml of drinking water) from days 3 to 21 post-infection. On day 5 post-infection, groups of mice were sacrificed for determination of viral DNA load, detection of ETA in brain homogenates and for in situ hybridization. The survival rate of mice was significantly increased when VACV was administered in combination with ETA (38.5% for VACV vs 78.6% for combined treatment; P = 0.04) although VACV or ETA alone had no significant effect compared to the vehicle. The benefit of combined therapy was still present when treatment was delayed until day 4 post-infection. The viral DNA load was significantly reduced in mice treated with VACV alone (P < 0.01) or combined with ETA (P < 0.05) compared to the uninfected group whereas ETA alone had no effect. These results reinforce the notion that both virus-induced and immune-related mechanisms participate in the pathogenesis of HSE and suggest that potent antiviral agent could be combined with immune-based therapy, such as a TNF-α inhibitor, to improve prognosis of HSE. PMID:24416771

  9. Terahertz-driven linear electron acceleration.

    PubMed

    Nanni, Emilio A; Huang, Wenqian R; Hong, Kyung-Han; Ravi, Koustuban; Fallahi, Arya; Moriena, Gustavo; Miller, R J Dwayne; Kärtner, Franz X

    2015-01-01

    The cost, size and availability of electron accelerators are dominated by the achievable accelerating gradient. Conventional high-brightness radio-frequency accelerating structures operate with 30-50 MeV m(-1) gradients. Electron accelerators driven with optical or infrared sources have demonstrated accelerating gradients orders of magnitude above that achievable with conventional radio-frequency structures. However, laser-driven wakefield accelerators require intense femtosecond sources and direct laser-driven accelerators suffer from low bunch charge, sub-micron tolerances and sub-femtosecond timing requirements due to the short wavelength of operation. Here we demonstrate linear acceleration of electrons with keV energy gain using optically generated terahertz pulses. Terahertz-driven accelerating structures enable high-gradient electron/proton accelerators with simple accelerating structures, high repetition rates and significant charge per bunch. These ultra-compact terahertz accelerators with extremely short electron bunches hold great potential to have a transformative impact for free electron lasers, linear colliders, ultrafast electron diffraction, X-ray science and medical therapy with X-rays and electron beams. PMID:26439410

  10. Terahertz-driven linear electron acceleration

    SciTech Connect

    Nanni, Emilio A.; Huang, Wenqian R.; Hong, Kyung-Han; Ravi, Koustuban; Fallahi, Arya; Moriena, Gustavo; Dwayne Miller, R. J.; Kärtner, Franz X.

    2015-10-06

    The cost, size and availability of electron accelerators are dominated by the achievable accelerating gradient. Conventional high-brightness radio-frequency accelerating structures operate with 30–50 MeVm-1 gradients. Electron accelerators driven with optical or infrared sources have demonstrated accelerating gradients orders of magnitude above that achievable with conventional radio-frequency structures. However, laser-driven wakefield accelerators require intense femtosecond sources and direct laser-driven accelerators suffer from low bunch charge, sub-micron tolerances and sub-femtosecond timing requirements due to the short wavelength of operation. Here we demonstrate linear acceleration of electrons with keV energy gain using optically generated terahertz pulses. Terahertz-driven accelerating structures enable high-gradient electron/proton accelerators with simple accelerating structures, high repetition rates and significant charge per bunch. As a result, these ultra-compact terahertz accelerators with extremely short electron bunches hold great potential to have a transformative impact for free electron lasers, linear colliders, ultrafast electron diffraction, X-ray science and medical therapy with X-rays and electron beams.

  11. Terahertz-driven linear electron acceleration

    PubMed Central

    Nanni, Emilio A.; Huang, Wenqian R.; Hong, Kyung-Han; Ravi, Koustuban; Fallahi, Arya; Moriena, Gustavo; Dwayne Miller, R. J.; Kärtner, Franz X.

    2015-01-01

    The cost, size and availability of electron accelerators are dominated by the achievable accelerating gradient. Conventional high-brightness radio-frequency accelerating structures operate with 30–50 MeV m−1 gradients. Electron accelerators driven with optical or infrared sources have demonstrated accelerating gradients orders of magnitude above that achievable with conventional radio-frequency structures. However, laser-driven wakefield accelerators require intense femtosecond sources and direct laser-driven accelerators suffer from low bunch charge, sub-micron tolerances and sub-femtosecond timing requirements due to the short wavelength of operation. Here we demonstrate linear acceleration of electrons with keV energy gain using optically generated terahertz pulses. Terahertz-driven accelerating structures enable high-gradient electron/proton accelerators with simple accelerating structures, high repetition rates and significant charge per bunch. These ultra-compact terahertz accelerators with extremely short electron bunches hold great potential to have a transformative impact for free electron lasers, linear colliders, ultrafast electron diffraction, X-ray science and medical therapy with X-rays and electron beams. PMID:26439410

  12. Terahertz-driven linear electron acceleration

    NASA Astrophysics Data System (ADS)

    Nanni, Emilio A.; Huang, Wenqian R.; Hong, Kyung-Han; Ravi, Koustuban; Fallahi, Arya; Moriena, Gustavo; Dwayne Miller, R. J.; Kärtner, Franz X.

    2015-10-01

    The cost, size and availability of electron accelerators are dominated by the achievable accelerating gradient. Conventional high-brightness radio-frequency accelerating structures operate with 30-50 MeV m-1 gradients. Electron accelerators driven with optical or infrared sources have demonstrated accelerating gradients orders of magnitude above that achievable with conventional radio-frequency structures. However, laser-driven wakefield accelerators require intense femtosecond sources and direct laser-driven accelerators suffer from low bunch charge, sub-micron tolerances and sub-femtosecond timing requirements due to the short wavelength of operation. Here we demonstrate linear acceleration of electrons with keV energy gain using optically generated terahertz pulses. Terahertz-driven accelerating structures enable high-gradient electron/proton accelerators with simple accelerating structures, high repetition rates and significant charge per bunch. These ultra-compact terahertz accelerators with extremely short electron bunches hold great potential to have a transformative impact for free electron lasers, linear colliders, ultrafast electron diffraction, X-ray science and medical therapy with X-rays and electron beams.

  13. Phase motion of accelerated electrons in vacuum laser acceleration

    SciTech Connect

    Hua, J. F.; Lin, Y. Z.; Tang, Ch. X.; Ho, Y. K.; Kong, Q.

    2007-01-15

    The phase stability in the capture and acceleration scenario (CAS) is studied and compared with that of conventional linear electron accelerators (CLEAs). For the CAS case, it has been found that a slow phase slippage occurs due to the difference between the electron velocity and the phase velocity of the longitudinal accelerating electric field. Thus, CAS electrons cannot remain in a fixed small phase region of the accelerating field to obtain a quasimonoenergy gain in contrast to the stability of phase oscillation in CLEAs. Also, the energy spread of the output electron beam for the CAS case cannot be kept as small as the CLEA because there is no good phase bunching phenomenon generated by phase oscillation.

  14. Accelerated discovery via a whole-cell model.

    PubMed

    Sanghvi, Jayodita C; Regot, Sergi; Carrasco, Silvia; Karr, Jonathan R; Gutschow, Miriam V; Bolival, Benjamin; Covert, Markus W

    2013-12-01

    To test the promise of whole-cell modeling to facilitate scientific inquiry, we compared growth rates simulated in a whole-cell model with experimental measurements for all viable single-gene disruption Mycoplasma genitalium strains. Discrepancies between simulations and experiments led to predictions about kinetic parameters of specific enzymes that we subsequently validated. These findings represent, to our knowledge, the first application of whole-cell modeling to accelerate biological discovery. PMID:24185838

  15. The comparative analysis of satisfaction rate among the public universities talented students with education and all the services provided to them

    PubMed Central

    Nikneshan, Shaghayegh; Yamani, Nikoo; Moghadam, Azam; Nasr, Ahmadreza

    2012-01-01

    Introduction: Universities provide different facilities for talented students. The aim of this research was to comparatively examine the rate of satisfaction among the talented students with the services offered to them at different Iranian universities. Methods: This was a survey study in which a researcher-made questionnaire was used to collect the data. The statistical population of this research consisted of all the talented students at four universities who had been admitted at these universities from 2003 to 2009. Using the formula, the total number of samples was estimated to be approximately 328. Results: The research findings indicated that the talented students did not have satisfaction with the educational situation, and no statistically significant difference was observed among the different universities with regard to this issue. Conclusion: According to the findings it is suggested that universities offer more financial facilities for research, and attending conferences, and provide rich-content and valuable classes, and active and creative teaching methods. It is also proposed that educational workshops on detecting talented students and the manner of dealing with them be convened for faculty members. PMID:23555129

  16. Comparative effect of partial root-zone drying and deficit irrigation on incidence of blossom-end rot in tomato under varied calcium rates

    PubMed Central

    Sun, Yanqi; Feng, Hao; Liu, Fulai

    2013-01-01

    This study investigated the comparative effects of reduced irrigation regimes—partial root-zone drying (PRD) and conventional deficit irrigation (DI)—on the incidence of blossom-end rot (BER) in tomato (Solanum lycopersicum L.) under three Ca-fertilization rates: 0, 100, and 200mg Ca kg–1 soil (denoted Ca0, Ca1, and Ca2, respectively). The plants were grown in split-root pots in a climate-controlled glasshouse and treated with PRD and DI during early flowering to the fruit maturity stage. The results showed that, in comparison with DI treatment, PRD significantly reduced BER incidence. A greater xylem sap abscisic acid concentration, lower stomatal conductance, and higher plant water status in the PRD in relation to the DI plants might have contributed to the increased fruit Ca uptake, and could have reduced BER development in tomato fruits. Therefore, under conditions with limited freshwater resources, application of PRD irrigation could